From bd82e6dfcf2d047c7916d67e8d931eeec757998a Mon Sep 17 00:00:00 2001
From: Abigail <abigail@abigail.freedom.nl>
Date: Mon, 10 Jan 2022 15:56:40 +0100
Subject: Week 147. Perl solutions

---
 challenge-147/abigail/perl/ch-1.pl     | 49 +++++++++++++++++++++++++++++++
 challenge-147/abigail/perl/ch-2.pl     | 53 ++++++++++++++++++++++++++++++++++
 challenge-147/abigail/t/ctest.ini      |  8 +++++
 challenge-147/abigail/t/input-1-1      |  0
 challenge-147/abigail/t/input-2-1      |  0
 challenge-147/abigail/t/output-1-1.exp |  1 +
 challenge-147/abigail/t/output-2-1.exp |  1 +
 7 files changed, 112 insertions(+)
 create mode 100644 challenge-147/abigail/perl/ch-1.pl
 create mode 100644 challenge-147/abigail/perl/ch-2.pl
 create mode 100644 challenge-147/abigail/t/ctest.ini
 create mode 100644 challenge-147/abigail/t/input-1-1
 create mode 100644 challenge-147/abigail/t/input-2-1
 create mode 100644 challenge-147/abigail/t/output-1-1.exp
 create mode 100644 challenge-147/abigail/t/output-2-1.exp

diff --git a/challenge-147/abigail/perl/ch-1.pl b/challenge-147/abigail/perl/ch-1.pl
new file mode 100644
index 0000000000..4e75524897
--- /dev/null
+++ b/challenge-147/abigail/perl/ch-1.pl
@@ -0,0 +1,49 @@
+#!/opt/perl/bin/perl
+
+use 5.032;
+
+use strict;
+use warnings;
+no  warnings 'syntax';
+
+use experimental 'signatures';
+use experimental 'lexical_subs';
+
+#
+# See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+#
+
+#
+# Run as: perl ch-1.pl
+#
+
+#
+# This is asking for the first 20 terms of A024785, which we can just
+# grab from https://oeis.org/A024785/list.
+#
+# Or we port the Python code from https://oeis.org/A024785
+#
+
+use Math::Prime::Util qw [is_prime];
+
+my @todo  = qw [2 3 5 7];
+my $count = 20;
+
+print "$_ " for @todo;
+$count -= @todo;
+
+MAIN: while (@todo) {
+    my @next;
+    for my $d (1 .. 9) {
+        foreach my $p (@todo) {
+            my $candidate = "$d$p";
+            next unless is_prime ($candidate);
+            print "$candidate ";
+            last MAIN if -- $count <= 0;
+            push @next   => $candidate;
+        }
+    }
+    @todo = @next;
+}
+
+print "\n";
diff --git a/challenge-147/abigail/perl/ch-2.pl b/challenge-147/abigail/perl/ch-2.pl
new file mode 100644
index 0000000000..e4ed1d17e9
--- /dev/null
+++ b/challenge-147/abigail/perl/ch-2.pl
@@ -0,0 +1,53 @@
+#!/opt/perl/bin/perl
+
+use 5.032;
+
+use strict;
+use warnings;
+no  warnings 'syntax';
+
+use experimental 'signatures';
+use experimental 'lexical_subs';
+
+#
+# See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+#
+
+#
+# Run as: perl ch-2.pl
+#
+
+#
+# We solve this by checking every pentagon number in order to see
+# whether it can be written as a sum of two (smaller) pentagon
+# numbers. If so, if their difference is a pentagon number, we
+# have the winning pair. We'll use a hash which tracks the pentagon
+# numbers seen so far.
+#
+# To calculate the next pentagon number, we will avoid division
+# (and multiplication).
+#
+# If P (N) == N * (3 * N - 1) / 2, then
+#
+# P (N + 1) == (N + 1) * (3 * (N + 1) - 1) / 2
+#           == ((N + 1) * (3 * N + 2) / 2
+#           == (3 * N * N + 5 * N + 2) / 2
+#           == (3 * N * N - N + 6 * N + 2) / 2
+#           == (N * (3 * N - 1) / 2) + ((6 * N + 2) / 2)
+#           == P (N) + 3 * N + 1
+#           == P (N) + N + N + N + 1
+#
+
+my %pentagon;
+
+MAIN: for (;;) {
+    state $n = 0;
+    state $p = 0;
+    $pentagon {$p += $n + $n + $n ++ + 1} ++;
+
+    $_ + $_ < $p && $pentagon  {$p - $_}
+                 && $pentagon  {$p - $_ - $_}
+                 && say ("$_ ", $p - $_)
+                 && last MAIN for keys %pentagon;
+}
+
diff --git a/challenge-147/abigail/t/ctest.ini b/challenge-147/abigail/t/ctest.ini
new file mode 100644
index 0000000000..bfef483d85
--- /dev/null
+++ b/challenge-147/abigail/t/ctest.ini
@@ -0,0 +1,8 @@
+# 
+# Configuration file for running tests, using ctest.
+# See https://github.com/Abigail/Misc/blob/master/ctest
+# 
+
+[names]
+1-1 = Fixed Output
+2-1 = Fixed Output
diff --git a/challenge-147/abigail/t/input-1-1 b/challenge-147/abigail/t/input-1-1
new file mode 100644
index 0000000000..e69de29bb2
diff --git a/challenge-147/abigail/t/input-2-1 b/challenge-147/abigail/t/input-2-1
new file mode 100644
index 0000000000..e69de29bb2
diff --git a/challenge-147/abigail/t/output-1-1.exp b/challenge-147/abigail/t/output-1-1.exp
new file mode 100644
index 0000000000..3648c94b73
--- /dev/null
+++ b/challenge-147/abigail/t/output-1-1.exp
@@ -0,0 +1 @@
+2 3 5 7 13 17 23 37 43 47 53 67 73 83 97 113 137 167 173 197
diff --git a/challenge-147/abigail/t/output-2-1.exp b/challenge-147/abigail/t/output-2-1.exp
new file mode 100644
index 0000000000..de3d6ccd8a
--- /dev/null
+++ b/challenge-147/abigail/t/output-2-1.exp
@@ -0,0 +1 @@
+1560090 7042750
-- 
cgit 


From 3617a4290d0ceff2af483943e103d3ec71ae2874 Mon Sep 17 00:00:00 2001
From: Abigail <abigail@abigail.freedom.nl>
Date: Mon, 10 Jan 2022 17:46:33 +0100
Subject: Week 147: awk solutions

---
 challenge-147/abigail/awk/ch-1.awk | 52 ++++++++++++++++++++++++++++++++++++++
 challenge-147/abigail/awk/ch-2.awk | 26 +++++++++++++++++++
 2 files changed, 78 insertions(+)
 create mode 100644 challenge-147/abigail/awk/ch-1.awk
 create mode 100644 challenge-147/abigail/awk/ch-2.awk

diff --git a/challenge-147/abigail/awk/ch-1.awk b/challenge-147/abigail/awk/ch-1.awk
new file mode 100644
index 0000000000..c39dc35247
--- /dev/null
+++ b/challenge-147/abigail/awk/ch-1.awk
@@ -0,0 +1,52 @@
+#!/usr/bin/awk
+
+#
+# See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+#
+
+#
+# Run as: awk -f ch-1.awk
+#
+
+func is_prime (n, i) {
+    if (n % 2 == 0) {return 0}
+    for (i = 3; i <= sqrt (n); i += 2) {
+        if (n % i == 0) {
+            return 0
+        }
+    }
+    return 1
+}
+
+BEGIN {
+    todo [1] = 2
+    todo [2] = 3
+    todo [3] = 5
+    todo [4] = 7
+    n = 4
+    i = 1
+    count = 20 - n;
+
+    printf ("2 3 5 7 ")
+
+    low  = 1
+    high = n
+    while (count > 0) {
+        for (d = 1; d <= 9 && count > 0; d ++) {
+            for (i = low; i <= high && count > 0; i ++) {
+                candidate = d todo [i]
+                if (is_prime(candidate) == 1) {
+                    printf candidate " "
+                    count --;
+                    todo [++ n] = candidate;
+                }
+            }
+        }
+        low  = high + 1
+        high = n
+    }
+    printf ("\n")
+}
+
+
+
diff --git a/challenge-147/abigail/awk/ch-2.awk b/challenge-147/abigail/awk/ch-2.awk
new file mode 100644
index 0000000000..e071da78fc
--- /dev/null
+++ b/challenge-147/abigail/awk/ch-2.awk
@@ -0,0 +1,26 @@
+#!/usr/bin/awk
+
+#
+# See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+#
+
+#
+# Run as: awk -f ch-2.awk
+#
+
+BEGIN {
+    while (!done) {
+        p += n + n + n ++ + 1
+        pentagon [p] = 1
+
+        for (seen in pentagon) {
+            if (seen + seen < p && (p - seen)        in pentagon \
+                                && (p - seen - seen) in pentagon ) {
+                print seen, p - seen
+                done = 1
+                break
+            }
+        }
+    }
+}
+
-- 
cgit 


From 354215f8375796503461e4cb1d6cde02a566c4cf Mon Sep 17 00:00:00 2001
From: Abigail <abigail@abigail.freedom.nl>
Date: Mon, 10 Jan 2022 20:06:43 +0100
Subject: Week 147: bash solutions

---
 challenge-147/abigail/bash/ch-1.sh | 55 ++++++++++++++++++++++++++++++++++++++
 challenge-147/abigail/bash/ch-2.sh | 30 +++++++++++++++++++++
 2 files changed, 85 insertions(+)
 create mode 100644 challenge-147/abigail/bash/ch-1.sh
 create mode 100644 challenge-147/abigail/bash/ch-2.sh

diff --git a/challenge-147/abigail/bash/ch-1.sh b/challenge-147/abigail/bash/ch-1.sh
new file mode 100644
index 0000000000..1f5f09be50
--- /dev/null
+++ b/challenge-147/abigail/bash/ch-1.sh
@@ -0,0 +1,55 @@
+#!/bin/sh
+
+#
+# See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+#
+
+#
+# Run as: bash ch-1.sh
+#
+
+set -f
+
+function is_prime () {
+    local n=$1
+    local i
+    is_prime=1
+    if ((n > 2 && n % 2 == 0)) 
+    then is_prime=0
+    else for ((i = 3; i * i <= n && is_prime == 1; i += 2))
+         do  if ((n % i == 0))
+             then is_prime=0
+             fi
+         done
+    fi
+}
+
+todo=(2 3 5 7)
+count=20
+
+for p in "${todo[@]}"
+do  printf "$p "
+    ((count --))
+done
+
+
+while ((count > 0))
+do    next=()
+      for ((d = 1; d <= 9 && count > 0; d ++))
+      do  for p in "${todo[@]}"
+          do  candidate=$d$p
+              is_prime $candidate
+              if (($is_prime == 1))
+              then printf $candidate" "
+                   ((count --))
+                   next+=($candidate)
+                   if ((count <= 0))
+                   then break
+                   fi
+              fi
+          done
+     done
+     todo=("${next[@]}")
+done
+
+echo
diff --git a/challenge-147/abigail/bash/ch-2.sh b/challenge-147/abigail/bash/ch-2.sh
new file mode 100644
index 0000000000..f38223377d
--- /dev/null
+++ b/challenge-147/abigail/bash/ch-2.sh
@@ -0,0 +1,30 @@
+#!/bin/sh
+
+#
+# See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+#
+
+#
+# Run as: bash ch-2.sh
+#
+
+set -f
+
+declare -A pentagon
+
+# ((n = 0))
+# ((p = 0))
+
+while true
+do    ((p = p + n + n + n + 1))
+      ((n ++))
+      pentagon[$p]=1
+
+      for seen in "${!pentagon[@]}"
+      do  if ((seen + seen < p)) && [ -v pentagon[$((p - seen))] -a \
+                                      -v pentagon[$((p - seen - seen))] ]
+          then echo $seen" "$((p - seen))
+               break 2
+          fi
+      done
+done
-- 
cgit 


From 95d45c5753b63b7656a434973453dae12e227a6a Mon Sep 17 00:00:00 2001
From: Abigail <abigail@abigail.freedom.nl>
Date: Tue, 11 Jan 2022 01:12:49 +0100
Subject: Week 147: bc solutions

---
 challenge-147/abigail/bc/ch-1.bc | 57 ++++++++++++++++++++++++++++++++++++++++
 challenge-147/abigail/bc/ch-2.bc | 41 +++++++++++++++++++++++++++++
 2 files changed, 98 insertions(+)
 create mode 100644 challenge-147/abigail/bc/ch-1.bc
 create mode 100644 challenge-147/abigail/bc/ch-2.bc

diff --git a/challenge-147/abigail/bc/ch-1.bc b/challenge-147/abigail/bc/ch-1.bc
new file mode 100644
index 0000000000..52d5cdb0f0
--- /dev/null
+++ b/challenge-147/abigail/bc/ch-1.bc
@@ -0,0 +1,57 @@
+#!/usr/bin/bc
+
+#
+# See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+#
+
+#
+# Run as: bc ch-1.bc
+#
+
+define is_prime (p) {
+    auto d
+    if (p == 2) {return 1}
+    if (p % 2 == 0) {return 0}
+    for (d = 3; d * d <= p; d += 2) {
+        if (p % d == 0) {return 0}
+    }
+    return 1
+}
+
+todo [1] = 2
+todo [2] = 3
+todo [3] = 5
+todo [4] = 7
+high = 4
+
+for (i = 1; i <= high; i ++) {
+    print todo [i], " "
+}
+
+count = 20 - high
+
+pow = 10
+while (count > 0) {
+    new_high = 0
+    for (d = 1; d <= 9 && count > 0; d ++) {
+        for (i = 1; i <= high && count > 0; i ++) {
+            candidate = d * pow + todo [i]
+            if (is_prime (candidate)) {
+                print candidate, " "
+                new_high = new_high + 1
+                count = count - 1
+                next [new_high] = candidate
+            }
+        }
+    }
+    for (j = 1; j <= new_high; j ++) {
+        todo [j] = next [j]
+    }
+    high = new_high
+    pow = pow * 10
+}
+
+"
+"
+
+halt
diff --git a/challenge-147/abigail/bc/ch-2.bc b/challenge-147/abigail/bc/ch-2.bc
new file mode 100644
index 0000000000..6aee8ec9b4
--- /dev/null
+++ b/challenge-147/abigail/bc/ch-2.bc
@@ -0,0 +1,41 @@
+#!/usr/bin/bc
+
+#
+# See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+#
+
+#
+# Run as: bc ch-2.bc
+#
+
+define is_pentagonal (p) {
+    auto l, h, m
+    l = l
+    h = high
+    while (l <= h) {
+        m = (l + h) / 2
+        if (pentagon [m] == p) {return 1}
+        if (pentagon [m] <  p) {l = m + 1} else {h = m - 1}
+    }
+    return 0
+}
+
+while (!done) {
+    p = p + n + n + n + 1
+    n = n + 1
+    high = high + 1
+
+    pentagon [high] = p
+
+    for (i = 1; i <= high && pentagon [i] + pentagon [i] < p && !done; i ++) {
+        seen = pentagon [i]
+        
+        if (is_pentagonal (p - seen) && is_pentagonal (p - seen - seen)) {
+            print seen, " "
+            p - seen
+            done = 1
+        }
+    }
+}
+
+halt
-- 
cgit 


From 46a9f55050cb852410da9c80c7e248d8df0328a8 Mon Sep 17 00:00:00 2001
From: Abigail <abigail@abigail.freedom.nl>
Date: Tue, 11 Jan 2022 19:04:33 +0100
Subject: Week 147: C solutions

---
 challenge-147/abigail/c/ch-1.c | 70 ++++++++++++++++++++++++++++++++++++++++++
 challenge-147/abigail/c/ch-2.c | 66 +++++++++++++++++++++++++++++++++++++++
 2 files changed, 136 insertions(+)
 create mode 100644 challenge-147/abigail/c/ch-1.c
 create mode 100644 challenge-147/abigail/c/ch-2.c

diff --git a/challenge-147/abigail/c/ch-1.c b/challenge-147/abigail/c/ch-1.c
new file mode 100644
index 0000000000..d02433f475
--- /dev/null
+++ b/challenge-147/abigail/c/ch-1.c
@@ -0,0 +1,70 @@
+# include <stdlib.h>
+# include <stdio.h>
+# include <string.h>
+# include <stdbool.h>
+
+/*
+ * See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+ */
+
+/*
+ * Run as: cc -o ch-1.o ch-1.c; ./ch-1.o
+ */
+# define COUNT 20
+
+bool is_prime (int n) {
+    if (n % 2 == 0) {return n == 2;}
+    for (int i = 3; i * i <= n; i += 2) {
+        if (n % i == 0) {return false;}
+    }
+    return true;
+}
+
+int main (void) {
+    int * todo;
+    if ((todo = (int *) malloc (4 * sizeof (int))) == NULL) {
+        perror ("Malloc failed");
+        return (1);
+    }
+    todo [0]    = 2;
+    todo [1]    = 3;
+    todo [2]    = 5;
+    todo [3]    = 7;
+    size_t high = 4;
+
+    for (size_t i = 0; i < high; i ++) {
+        printf ("%d ", todo [i]);
+    }
+
+    int count = COUNT - high;
+
+    int pow = 10;
+    while (count > 0) {
+        int * next;
+        int next_high = 0;
+        if ((next = (int *) malloc (9 * high * sizeof (int))) == NULL) {
+            perror ("Malloc failed");
+            return (1);
+        }
+        for (int d = 1; d <= 9 && count > 0; d ++) {
+            for (size_t i = 0; i < high && count > 0; i ++) {
+                int candidate = d * pow + todo [i];
+                if (is_prime (candidate)) {
+                    next [next_high ++] = candidate;
+                    printf ("%d ", candidate);
+                    count --;
+                }
+            }
+        }
+        if (!next_high) {
+            break;
+        }
+        free (todo);
+        todo = next;
+        high = next_high;
+        pow *= 10;
+    }
+    free (todo);
+
+    printf ("\n");
+}
diff --git a/challenge-147/abigail/c/ch-2.c b/challenge-147/abigail/c/ch-2.c
new file mode 100644
index 0000000000..02ff39bd1e
--- /dev/null
+++ b/challenge-147/abigail/c/ch-2.c
@@ -0,0 +1,66 @@
+# include <stdlib.h>
+# include <stdio.h>
+# include <string.h>
+# include <stdbool.h>
+
+/*
+ * See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+ */
+
+/*
+ * Run as: cc -o ch-2.o ch-2.c; ./ch-2.o
+ */
+
+bool is_pentagonal (int candidate, int * pentagon, size_t max) {
+    size_t low  = 0;
+    size_t high = max;
+    while (low < high) {
+        size_t mid = (low + high) / 2;
+        if (pentagon [mid] == candidate) {return true;}
+        if (pentagon [mid]  < candidate) {low  = mid + 1;}
+        if (pentagon [mid]  > candidate) {high = mid;}
+    }
+    return false;
+}
+
+
+int main (void) {
+    int *  pentagon =  NULL;
+    int    n        =     0;
+    int    p        =     0;
+    size_t cap      =   100;
+    size_t high     =     0;
+    bool   done     = false;
+
+    if ((pentagon = (int *) malloc (cap * sizeof (int))) == NULL) {
+        perror ("Malloc failed");
+        return (1);
+    }
+
+    while (!done) {
+        p += n + n + n + 1;
+        n ++;
+        if (high >= cap) {
+            cap *= 2;
+            if ((pentagon =
+                     (int *) realloc (pentagon, cap * sizeof (int))) == NULL) {
+                perror ("Realloc failed");
+                return (1);
+            }
+        }
+        pentagon [high ++] = p;
+
+        for (size_t i = 0; i < high &&
+                           pentagon [i] + pentagon [i] < p &&
+                          !done; i ++) {
+            int seen = pentagon [i];
+            if (is_pentagonal (p - seen,        pentagon, high) &&
+                is_pentagonal (p - seen - seen, pentagon, high)) {
+                printf ("%d %d\n", seen, p - seen);
+                done = true;
+            }
+        }
+    }
+
+    return (0);
+}
-- 
cgit 


From 94cdbab3f1198c78a3dcedb9ada1a8596114cfcb Mon Sep 17 00:00:00 2001
From: drbaggy <js5@sanger.ac.uk>
Date: Wed, 12 Jan 2022 01:48:10 +0000
Subject: last unless replaced by ||last

---
 challenge-147/james-smith/README.md          | 4 ++--
 challenge-147/james-smith/perl/ch-1-right.pl | 2 +-
 challenge-147/james-smith/perl/ch-1.pl       | 4 ++--
 3 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/challenge-147/james-smith/README.md b/challenge-147/james-smith/README.md
index 6941c1b663..13e84e0c1b 100644
--- a/challenge-147/james-smith/README.md
+++ b/challenge-147/james-smith/README.md
@@ -49,7 +49,7 @@ my @tprimes_current = (3,7);
 printf $TEMPLATE, ++$index, $_, time-$t0 for 2,3,5,7;
 while(1) {
   # ** Stop if there are no primes of length `n`.
-  last unless @tprimes_current;
+  @tprimes_current||last;
   my @tprimes_new = ();
   # ** Loop through each of possible left-truncatable primes...
   for my $first ( 1..9 ) {
@@ -109,7 +109,7 @@ my @tprimes_current = (2,3,5,7);
 printf $TEMPLATE, ++$idx, $_, time - $t0 foreach @tprimes_current;
 
 for my $p ( 1 .. 100 ) {
-  last unless @tprimes_current;
+  @tprimes_current||last;
   my @tprimes_new = ();
   foreach my $base ( @tprimes_current ) {
     B: foreach my $last ( 1,3,7,9 ) {
diff --git a/challenge-147/james-smith/perl/ch-1-right.pl b/challenge-147/james-smith/perl/ch-1-right.pl
index 9565a26b0f..ef094dcf7b 100644
--- a/challenge-147/james-smith/perl/ch-1-right.pl
+++ b/challenge-147/james-smith/perl/ch-1-right.pl
@@ -12,7 +12,7 @@ my @tprimes_current = (2,3,5,7);
 printf $TEMPLATE, ++$idx, $_, time - $t0 foreach @tprimes_current;
 
 for my $p ( 1 .. 100 ) {
-  last unless @tprimes_current;
+  @tprimes_current||last;
   my @tprimes_new = ();
   foreach my $base ( @tprimes_current ) {
     B: foreach my $last ( 1,3,7,9 ) {
diff --git a/challenge-147/james-smith/perl/ch-1.pl b/challenge-147/james-smith/perl/ch-1.pl
index 3d9b2ccf72..2f0c0641cb 100644
--- a/challenge-147/james-smith/perl/ch-1.pl
+++ b/challenge-147/james-smith/perl/ch-1.pl
@@ -34,8 +34,8 @@ my @tprimes_current = (3,7);
 
 printf $T, ++$index, $_, time-$t0 for 2,3,5,7;
 while(1) {
-  last unless @tprimes_current; ## Exit if there are no current l-trunc primes
-                                ## We are at the end of the list...
+  @tprimes_current||last; ## Exit if there are no current l-trunc primes
+                          ## We are at the end of the list...
 
   my @tprimes_new = ();
 
-- 
cgit 


From a3f595d255809dfb78e43d0179cbefd67a5a1c62 Mon Sep 17 00:00:00 2001
From: Abigail <abigail@abigail.freedom.nl>
Date: Sat, 15 Jan 2022 16:30:51 +0100
Subject: Week 147: Go solutions

---
 challenge-147/abigail/go/ch-1.go | 56 ++++++++++++++++++++++++++++++++++++++++
 challenge-147/abigail/go/ch-2.go | 31 ++++++++++++++++++++++
 2 files changed, 87 insertions(+)
 create mode 100644 challenge-147/abigail/go/ch-1.go
 create mode 100644 challenge-147/abigail/go/ch-2.go

diff --git a/challenge-147/abigail/go/ch-1.go b/challenge-147/abigail/go/ch-1.go
new file mode 100644
index 0000000000..a71d770cb3
--- /dev/null
+++ b/challenge-147/abigail/go/ch-1.go
@@ -0,0 +1,56 @@
+package main
+
+//
+// See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+//
+
+//
+// Run as: go run ch-1.go
+//
+
+import (
+    "fmt"
+)
+
+func is_prime (num int) bool {
+    if num == 2 {
+        return true
+    }
+    if num % 2 == 0 {
+        return false
+    }
+    for i := 3; i * i <= num; i += 2 {
+        if num % i == 0 {
+            return false
+        }
+    }
+    return true
+}
+
+func main () {
+    todo := [] int {2, 3, 5, 7}
+    for _, n := range todo {
+        fmt . Printf ("%d ", n)
+    }
+    count := 20 - len (todo)
+    pow   := 10
+    for count > 0 && len (todo) > 0 {
+        new_todo := [] int {}
+        for d := 1; (d <= 9) && (count > 0); d ++ {
+            for _, p := range (todo) {
+                candidate := d * pow + p
+                if is_prime (candidate) {
+                    fmt . Printf ("%d ", candidate)
+                    new_todo = append (new_todo, candidate)
+                    count --
+                }
+                if count <= 0 {
+                    break
+                }
+            }
+        }
+        todo = new_todo
+        pow *= 10
+    }
+    fmt . Print ("\n")
+}
diff --git a/challenge-147/abigail/go/ch-2.go b/challenge-147/abigail/go/ch-2.go
new file mode 100644
index 0000000000..13fe915ad4
--- /dev/null
+++ b/challenge-147/abigail/go/ch-2.go
@@ -0,0 +1,31 @@
+package main
+
+//
+// See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+//
+
+//
+// Run as: go run ch-2.go
+//
+
+import (
+    "fmt"
+)
+
+func main () {
+    p := 0
+    n := 0
+    pentagon := map [int] bool { }
+    for {
+        p = p + n + n + n + 1
+        n ++
+        pentagon [p] = true
+        for seen := range pentagon {
+            if seen + seen < p && pentagon [p - seen] &&
+                                  pentagon [p - seen - seen] {
+                fmt . Printf ("%d %d\n", seen, p - seen)
+                return
+            }
+        }
+    }
+}
-- 
cgit 


From f6b8071c5ec3c2470b8e1ba37908648e0dbededc Mon Sep 17 00:00:00 2001
From: Abigail <abigail@abigail.freedom.nl>
Date: Sat, 15 Jan 2022 17:17:33 +0100
Subject: Week 147: Java solutions

---
 challenge-147/abigail/java/ch-1.java | 54 ++++++++++++++++++++++++++++++++++++
 challenge-147/abigail/java/ch-2.java | 32 +++++++++++++++++++++
 2 files changed, 86 insertions(+)
 create mode 100644 challenge-147/abigail/java/ch-1.java
 create mode 100644 challenge-147/abigail/java/ch-2.java

diff --git a/challenge-147/abigail/java/ch-1.java b/challenge-147/abigail/java/ch-1.java
new file mode 100644
index 0000000000..9b3b57be9e
--- /dev/null
+++ b/challenge-147/abigail/java/ch-1.java
@@ -0,0 +1,54 @@
+//
+// See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+//
+
+//
+// Run as: ln ch-1.java ch1.java; javac ch1.java; java ch1
+//
+
+import java.util.*;
+import java.util.ArrayList;
+
+public class ch1 {
+    public static boolean is_prime (int p) {
+        if (p == 2)     {return true;}
+        if (p % 2 == 0) {return false;}
+        for (int i = 3; i * i <= p; i += 2) {
+            if (p % i == 0) {return false;}
+        }
+        return (true);
+    }
+
+    public static void main (String [] args) {
+        ArrayList <Integer> todo = new ArrayList <Integer> ();
+        todo . add (2);
+        todo . add (3);
+        todo . add (5);
+        todo . add (7);
+        for (int p: todo) {
+            System . out . printf ("%d ", p);
+        }
+        int count = 20 - todo . size ();
+        int pow   = 10;
+      main:
+        while (todo . size () > 0) {
+            ArrayList <Integer> new_todo = new ArrayList <Integer> ();
+            for (int d = 1; d <= 9; d ++) {
+                for (int p: todo) {
+                    int candidate = d * pow + p;
+                    if (is_prime (candidate)) {
+                        System . out . printf ("%d ", candidate);
+                        new_todo . add (candidate);
+                        count --;
+                        if (count <= 0) {
+                            break main;
+                        }
+                    }
+                }
+            }
+            pow = pow * 10;
+            todo = new_todo;
+        }
+        System . out . print ("\n");
+    }
+}
diff --git a/challenge-147/abigail/java/ch-2.java b/challenge-147/abigail/java/ch-2.java
new file mode 100644
index 0000000000..5469775b97
--- /dev/null
+++ b/challenge-147/abigail/java/ch-2.java
@@ -0,0 +1,32 @@
+//
+// See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+//
+
+//
+// Run as: ln ch-2.java ch2.java; javac ch2.java; java ch2
+//
+
+import java.util.*;
+
+public class ch2 {
+    public static void main (String [] args) {
+        int p = 0;
+        int n = 0;
+        Map <Integer, Boolean> pentagon = new Hashtable <Integer, Boolean> ();
+        boolean done = false;
+        while (true) {
+            p += n + n + n + 1;
+            n ++;
+            pentagon . put (p, true);
+            for (Map . Entry <Integer, Boolean> entry: pentagon . entrySet ()) {
+                Integer seen = entry . getKey ();
+                if (seen + seen < p &&
+                    pentagon . containsKey (p - seen) &&
+                    pentagon . containsKey (p - seen - seen)) {
+                    System . out . printf ("%d %d\n", seen, p - seen);
+                    return;
+                }
+            }
+        }
+    }
+}
-- 
cgit 


From 0b93e274674688f3ae6702e168b0e0391c4a5bf5 Mon Sep 17 00:00:00 2001
From: Abigail <abigail@abigail.freedom.nl>
Date: Sat, 15 Jan 2022 19:47:06 +0100
Subject: Week 147: Lua solutions

---
 challenge-147/abigail/lua/ch-1.lua | 57 ++++++++++++++++++++++++++++++++++++++
 challenge-147/abigail/lua/ch-2.lua | 29 +++++++++++++++++++
 2 files changed, 86 insertions(+)
 create mode 100644 challenge-147/abigail/lua/ch-1.lua
 create mode 100644 challenge-147/abigail/lua/ch-2.lua

diff --git a/challenge-147/abigail/lua/ch-1.lua b/challenge-147/abigail/lua/ch-1.lua
new file mode 100644
index 0000000000..0c86152ba1
--- /dev/null
+++ b/challenge-147/abigail/lua/ch-1.lua
@@ -0,0 +1,57 @@
+#!/opt/local/bin/lua
+
+--
+-- See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+--
+
+--
+-- Run as: lua ch-1.lua
+--
+
+function is_prime (p)
+    if p == 2 then
+        return true
+    end
+    if p % 2 == 0 then
+        return false
+    end
+    i = 3
+    while i * i <= p do
+        if p % i == 0 then
+            return false
+        end
+        i = i + 2
+    end
+    return true
+end
+
+todo = {2, 3, 5, 7}
+for i, p in ipairs (todo) do
+    io . write (p, " ")
+end
+
+count = 20 - #todo
+
+pow = 10
+while #todo > 0 do
+    new_todo = {}
+    for d = 1, 9 do
+        for i, p in ipairs (todo) do
+            candidate = d * pow + p
+            if is_prime (candidate) then
+                io . write (candidate, " ")
+                new_todo [#new_todo + 1] = candidate
+                count = count - 1
+                if count <= 0 then
+                    goto end_of_while
+                end
+            end
+        end
+    end
+    todo = new_todo
+    pow  = pow * 10
+end
+
+::end_of_while::
+
+io . write ("\n")
diff --git a/challenge-147/abigail/lua/ch-2.lua b/challenge-147/abigail/lua/ch-2.lua
new file mode 100644
index 0000000000..1d93585f24
--- /dev/null
+++ b/challenge-147/abigail/lua/ch-2.lua
@@ -0,0 +1,29 @@
+#!/opt/local/bin/lua
+
+--
+-- See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+--
+
+--
+-- Run as: lua ch-2.lua
+--
+
+pentagon = {}
+p = 0
+n = 0
+
+while true do
+    p = p + n + n + n + 1
+    n = n + 1
+    pentagon [p] = 1
+    for seen in pairs (pentagon) do
+        if seen + seen <= p and pentagon [p - seen]        ~= nil
+                            and pentagon [p - seen - seen] ~= nil then
+            print (seen .. " " .. (p - seen))
+            goto end_of_while
+        end
+    end
+end
+
+::end_of_while:: 
+
-- 
cgit 


From 3675e785bd1ddadcff97eb6725e1466eb1738f7a Mon Sep 17 00:00:00 2001
From: Abigail <abigail@abigail.freedom.nl>
Date: Sat, 15 Jan 2022 19:59:11 +0100
Subject: Week 147: Node.js solutions

---
 challenge-147/abigail/node/ch-1.js | 47 ++++++++++++++++++++++++++++++++++++++
 challenge-147/abigail/node/ch-2.js | 29 +++++++++++++++++++++++
 2 files changed, 76 insertions(+)
 create mode 100644 challenge-147/abigail/node/ch-1.js
 create mode 100644 challenge-147/abigail/node/ch-2.js

diff --git a/challenge-147/abigail/node/ch-1.js b/challenge-147/abigail/node/ch-1.js
new file mode 100644
index 0000000000..2a6c5c3764
--- /dev/null
+++ b/challenge-147/abigail/node/ch-1.js
@@ -0,0 +1,47 @@
+#!/usr/local/bin/node
+
+//
+// See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+//
+
+//
+// Run as: node ch-1.js
+//
+
+function is_prime (p) {
+    if (p == 2) {return true}
+    if (p % 2 == 0) {return false}
+    for (let i = 3; i * i <= p; i += 2) {
+        if (p % i == 0) {return false}
+    }
+    return true
+}
+
+let todo  = [2, 3, 5, 7]
+let count = 20 - todo . length
+
+todo . forEach (p => process . stdout . write (p . toString () + " "))
+
+let pow = 10
+main: {
+    while (todo . length > 0) {
+        let new_todo = []
+        for (let d = 1; d <= 9; d ++) {
+            for (let i = 0; i < todo . length; i ++) {
+                let candidate = d * pow + todo [i]
+                if (is_prime (candidate)) {
+                    new_todo . push (candidate)
+                    process . stdout . write (candidate . toString () + " ")
+                    count --
+                    if (count <= 0) {
+                        break main
+                    }
+                }
+            }
+        }
+        todo = new_todo
+        pow *= 10
+    }
+}
+
+process . stdout . write ("\n")
diff --git a/challenge-147/abigail/node/ch-2.js b/challenge-147/abigail/node/ch-2.js
new file mode 100644
index 0000000000..e06832ee9b
--- /dev/null
+++ b/challenge-147/abigail/node/ch-2.js
@@ -0,0 +1,29 @@
+#!/usr/local/bin/node
+
+//
+// See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+//
+
+//
+// Run as: node ch-2.js
+//
+
+let pentagon = {}
+let p = 0
+let n = 0
+
+main: {
+    while (1) {
+        p += n + n + n + 1
+        n ++
+        pentagon [p] = 1
+        for (let seen in pentagon) {
+            seen = +seen
+            if (seen + seen <= p && (p - seen)        in pentagon &&
+                                    (p - seen - seen) in pentagon) {
+                console . log (seen . toString () + " " + (p - seen))
+                break main
+            }
+        }
+    }
+}
-- 
cgit 


From 229529902e59d78ca79aebf2e8a42ef1382cfa1d Mon Sep 17 00:00:00 2001
From: Abigail <abigail@abigail.freedom.nl>
Date: Sat, 15 Jan 2022 22:28:24 +0100
Subject: Week 147: Pascal solutions

---
 challenge-147/abigail/pascal/ch-1.p | 82 +++++++++++++++++++++++++++++++++++++
 challenge-147/abigail/pascal/ch-2.p | 41 +++++++++++++++++++
 2 files changed, 123 insertions(+)
 create mode 100644 challenge-147/abigail/pascal/ch-1.p
 create mode 100644 challenge-147/abigail/pascal/ch-2.p

diff --git a/challenge-147/abigail/pascal/ch-1.p b/challenge-147/abigail/pascal/ch-1.p
new file mode 100644
index 0000000000..24dc514652
--- /dev/null
+++ b/challenge-147/abigail/pascal/ch-1.p
@@ -0,0 +1,82 @@
+Program XXX;
+
+(*                                                                   *)
+(* See https://theweeklychallenge.org/blog/perl-weekly-challenge-147 *)
+(*                                                                   *)
+
+(*                                           *)
+(* Run as: fpc -och-1.out ch-1.p; ./ch-1.out *)
+(*                                           *)
+
+var
+    todo: array of integer;
+    new_todo: array of integer;
+    pow, i, d: integer;
+    count: integer = 20;
+    candidate: integer;
+
+function is_prime (p: integer): boolean;
+    var
+        i: integer;
+
+    begin
+        if p = 2 then begin
+            is_prime := true;
+            exit;
+        end;
+        if p mod 2 = 0 then begin
+            is_prime := false;
+            exit;
+        end;
+        i := 3;
+        while i * i <= p do begin
+            if p mod i = 0 then begin
+                is_prime := false;
+                exit;
+            end;
+            i := i + 2;
+        end;
+        is_prime := true;
+        exit;
+    end;
+    
+
+begin
+    setlength (todo, 4);
+    todo [0] := 2;
+    todo [1] := 3;
+    todo [2] := 5;
+    todo [3] := 7;
+    for i := 0 to 3 do begin
+        write (todo [i], ' ');
+    end;
+    count := count - 4;
+    pow   := 10;
+    while count > 0 do begin
+        setlength (new_todo, 0);
+        for d := 1 to 9 do begin
+            for i := 0 to length (todo) - 1 do begin
+                candidate := d * pow + todo [i];
+                if is_prime (candidate) then begin
+                    insert (candidate, new_todo, length (new_todo));
+                    write (candidate, ' ');
+                    count := count - 1;
+                    if count <= 0 then begin
+                        break;
+                    end;
+                end;
+                if count <= 0 then begin
+                    break;
+                end;
+            end;
+            if count <= 0 then begin
+                break;
+            end;
+        end;
+        todo := new_todo;
+        pow  := pow * 10;
+    end;
+    writeln ('');
+end.
+
+end.
diff --git a/challenge-147/abigail/pascal/ch-2.p b/challenge-147/abigail/pascal/ch-2.p
new file mode 100644
index 0000000000..ac8d08d076
--- /dev/null
+++ b/challenge-147/abigail/pascal/ch-2.p
@@ -0,0 +1,41 @@
+Program ch2;
+
+(*                                                                   *)
+(* See https://theweeklychallenge.org/blog/perl-weekly-challenge-147 *)
+(*                                                                   *)
+
+(*                                           *)
+(* Run as: fpc -och-2.out ch-2.p; ./ch-2.out *)
+(*                                           *)
+
+uses
+    fgl;
+
+var
+    pentagon: specialize TFPGMap <longint, boolean>;
+    n, p, seen, i: longint;
+    done: boolean;
+
+begin
+    pentagon := specialize TFPGMap <longint, boolean> . Create;
+    p := 0;
+    n := 0;
+    done := false;
+    while not done do begin
+        p := p + n + n + n + 1;
+        n := n + 1;
+        pentagon . Add (p, true);
+        for i := 0 to pentagon . count - 1 do begin
+            seen := pentagon . Keys [i];
+            if (seen + seen <= p)                    and
+               (pentagon . IndexOf (p - seen) >= 0)  and
+               (pentagon . IndexOf (p - seen - seen) >= 0) then begin
+                writeln (seen, ' ', p - seen);
+                done := true;
+            end;
+            if done then begin
+                break;
+            end;
+        end
+    end
+end.
-- 
cgit 


From 4b1c4fc7e1809c724d3d994f0de6d97c4a14b415 Mon Sep 17 00:00:00 2001
From: Abigail <abigail@abigail.freedom.nl>
Date: Sun, 16 Jan 2022 13:28:01 +0100
Subject: Week 147: Python solutions

---
 challenge-147/abigail/python/ch-1.py | 37 ++++++++++++++++++++++++++++++++++++
 challenge-147/abigail/python/ch-2.py | 29 ++++++++++++++++++++++++++++
 2 files changed, 66 insertions(+)
 create mode 100644 challenge-147/abigail/python/ch-1.py
 create mode 100644 challenge-147/abigail/python/ch-2.py

diff --git a/challenge-147/abigail/python/ch-1.py b/challenge-147/abigail/python/ch-1.py
new file mode 100644
index 0000000000..cd317b880b
--- /dev/null
+++ b/challenge-147/abigail/python/ch-1.py
@@ -0,0 +1,37 @@
+#!/usr/local/bin/python3
+
+#
+# See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+#
+
+#
+# Run as: python ch-1.py
+#
+
+import sys
+from sympy import isprime
+
+todo = [2, 3, 5, 7]
+[sys . stdout . write (str (x) + " ") for x in todo]
+count = 20 - len (todo)
+
+pow = 10
+while count > 0:
+    new_todo = []
+    for d in range (1, 10):
+        for p in todo:
+            candidate = d * pow + p
+            if isprime (candidate):
+                sys . stdout . write (str (candidate) + " ")
+                count = count - 1
+                new_todo . append (candidate)
+                if count <= 0:
+                    break
+            if count <= 0:
+                break
+        if count <= 0:
+            break
+    todo = new_todo
+    pow  = pow * 10
+
+sys . stdout . write ("\n")
diff --git a/challenge-147/abigail/python/ch-2.py b/challenge-147/abigail/python/ch-2.py
new file mode 100644
index 0000000000..9d8ae317b3
--- /dev/null
+++ b/challenge-147/abigail/python/ch-2.py
@@ -0,0 +1,29 @@
+#!/usr/local/bin/python3
+
+#
+# See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+#
+
+#
+# Run as: python ch-2.py
+#
+
+pentagon = {}
+p = 0
+n = 0
+done = False
+
+
+while not done:
+    p = p + n + n + n + 1
+    n = n + 1
+    pentagon [p] = True
+
+    for seen in pentagon:
+        if seen + seen <= p and (p - seen) in pentagon \
+                            and (p - seen - seen) in pentagon:
+            print (seen, p - seen)
+            done = True
+            break
+        if done:
+            break
-- 
cgit 


From 6a42ef0f1bfd7b33cd271aff9a0323cf97620bad Mon Sep 17 00:00:00 2001
From: Abigail <abigail@abigail.freedom.nl>
Date: Sun, 16 Jan 2022 17:42:00 +0100
Subject: Week 147: R solutions

---
 challenge-147/abigail/r/ch-1.r | 46 ++++++++++++++++++++++++++++++++++++++++++
 challenge-147/abigail/r/ch-2.r | 37 +++++++++++++++++++++++++++++++++
 2 files changed, 83 insertions(+)
 create mode 100644 challenge-147/abigail/r/ch-1.r
 create mode 100644 challenge-147/abigail/r/ch-2.r

diff --git a/challenge-147/abigail/r/ch-1.r b/challenge-147/abigail/r/ch-1.r
new file mode 100644
index 0000000000..ef6dddc678
--- /dev/null
+++ b/challenge-147/abigail/r/ch-1.r
@@ -0,0 +1,46 @@
+#!/usr/local/bin/Rscript
+
+#
+# See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+#
+
+#
+# Run as: Rscript ch-1.r
+#
+
+suppressPackageStartupMessages (
+    library (gmp)
+)
+
+todo = c (2, 3, 5, 7)
+cat (todo, "")
+
+count = 20 - length (todo)
+
+pow = 10
+while (count > 0 && length (todo) > 0) {
+    new_todo = c ()
+    for (d in 1 : 9) {
+        for (p in todo) {
+            candidate = d * pow + p
+            if (isprime (candidate) > 0) {
+                cat (candidate, "")
+                count = count - 1
+                new_todo = c (new_todo, candidate)
+                if (count <= 0) {
+                    break
+                }
+            }
+            if (count <= 0) {
+                break
+            }
+        }
+        if (count <= 0) {
+            break
+        }
+    }
+    pow = pow * 10
+    todo = new_todo
+}
+
+cat ("\n")
diff --git a/challenge-147/abigail/r/ch-2.r b/challenge-147/abigail/r/ch-2.r
new file mode 100644
index 0000000000..5ae1bf82e5
--- /dev/null
+++ b/challenge-147/abigail/r/ch-2.r
@@ -0,0 +1,37 @@
+#!/usr/local/bin/Rscript
+
+#
+# See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+#
+
+#
+# Run as: Rscript ch-2.r
+#
+
+suppressPackageStartupMessages (
+    library (hash)
+)
+
+pentagon <- hash ()
+p        <- 0
+n        <- 0
+done     <- FALSE
+
+while (!done) {
+    p <- p + n + n + n + 1
+    n <- n + 1
+    .set (pentagon, p, 1)
+
+    for (seen in keys (pentagon)) {
+        seen <- as.numeric (seen)
+        if (seen + seen <= p &&
+              all (has.key (c (as.character (p - seen),
+                               as.character (p - seen - seen)), pentagon))) {
+            cat (seen, p - seen, "\n")
+            done = TRUE
+        }
+        if (done) {
+            break
+        }
+    }
+}
-- 
cgit 


From 0cbed3d1cd8b789156d383d62f25a2ebaff00371 Mon Sep 17 00:00:00 2001
From: Abigail <abigail@abigail.freedom.nl>
Date: Sun, 16 Jan 2022 19:03:20 +0100
Subject: Week 147: Ruby solutions

---
 challenge-147/abigail/ruby/ch-1.rb | 49 ++++++++++++++++++++++++++++++++++++++
 challenge-147/abigail/ruby/ch-2.rb | 30 +++++++++++++++++++++++
 2 files changed, 79 insertions(+)
 create mode 100644 challenge-147/abigail/ruby/ch-1.rb
 create mode 100644 challenge-147/abigail/ruby/ch-2.rb

diff --git a/challenge-147/abigail/ruby/ch-1.rb b/challenge-147/abigail/ruby/ch-1.rb
new file mode 100644
index 0000000000..0e0eaffc4b
--- /dev/null
+++ b/challenge-147/abigail/ruby/ch-1.rb
@@ -0,0 +1,49 @@
+#!/usr/bin/ruby
+
+#
+# See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+#
+ 
+#
+# Run as: ruby ch-1.rb
+#
+
+require 'prime'
+
+todo = [2, 3, 5, 7];
+
+todo . each do
+    | x |
+    print (x . to_s + " ")
+end
+
+count = 20 - todo . length
+
+pow = 10
+while todo . length > 0 && count > 0 do
+    new_todo = []
+    for d in 1 .. 9 do
+        todo . each do
+            | p |
+            candidate = d * pow + p
+            if (Prime . prime? (candidate)) then
+                new_todo . push (candidate)
+                print (candidate . to_s + " ")
+                count = count - 1
+                if (count <= 0) then
+                    break
+                end
+            end
+            if (count <= 0) then
+                break
+            end
+        end
+        if (count <= 0) then
+            break
+        end
+    end
+    pow = pow * 10
+    todo = new_todo
+end
+
+puts ("")
diff --git a/challenge-147/abigail/ruby/ch-2.rb b/challenge-147/abigail/ruby/ch-2.rb
new file mode 100644
index 0000000000..a3dbb601cc
--- /dev/null
+++ b/challenge-147/abigail/ruby/ch-2.rb
@@ -0,0 +1,30 @@
+#!/usr/bin/ruby
+
+#
+# See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+#
+ 
+#
+# Run as: ruby ch-2.rb
+#
+
+pentagon = {}
+p = 0
+n = 0
+done = false
+
+
+while not done do
+    p = p + n + n + n + 1
+    n = n + 1
+    pentagon [p] = true
+    pentagon . each do
+        | seen, _ |
+        if (seen + seen <= p && pentagon . key?(p - seen) \
+                             && pentagon . key?(p - seen - seen)) then
+            puts (seen . to_s + " " + (p - seen) . to_s)
+            done = true
+            break
+        end
+    end
+end
-- 
cgit 


From 4d99862bf4e64b7a33d5c5bc52a4b9b5b9ab109d Mon Sep 17 00:00:00 2001
From: Abigail <abigail@abigail.freedom.nl>
Date: Sun, 16 Jan 2022 19:31:17 +0100
Subject: Week 147: Hello, World solutions.

---
 challenge-147/abigail/basic/ch-1.bas       |  9 +++++++++
 challenge-147/abigail/befunge-93/ch-1.bf93 |  2 ++
 challenge-147/abigail/cobol/ch-1.cb        | 14 ++++++++++++++
 challenge-147/abigail/csh/ch-1.csh         | 11 +++++++++++
 challenge-147/abigail/erlang/ch-1.erl      | 15 +++++++++++++++
 challenge-147/abigail/forth/ch-1.fs        |  5 +++++
 challenge-147/abigail/fortran/ch-1.f90     | 12 ++++++++++++
 challenge-147/abigail/m4/ch-1.m4           |  1 +
 challenge-147/abigail/mmix/ch-1.mms        | 17 +++++++++++++++++
 challenge-147/abigail/ocaml/ch-1.ml        |  9 +++++++++
 challenge-147/abigail/php/ch-1.php         | 11 +++++++++++
 challenge-147/abigail/postscript/ch-1.ps   | 10 ++++++++++
 challenge-147/abigail/rexx/ch-1.rexx       |  9 +++++++++
 challenge-147/abigail/scheme/ch-1.scm      | 12 ++++++++++++
 challenge-147/abigail/sed/ch-1.sed         | 12 ++++++++++++
 challenge-147/abigail/sql/ch-1.sql         |  9 +++++++++
 challenge-147/abigail/t/input-1-1          |  1 +
 challenge-147/abigail/tcl/ch-1.tcl         | 11 +++++++++++
 18 files changed, 170 insertions(+)
 create mode 100644 challenge-147/abigail/basic/ch-1.bas
 create mode 100644 challenge-147/abigail/befunge-93/ch-1.bf93
 create mode 100644 challenge-147/abigail/cobol/ch-1.cb
 create mode 100644 challenge-147/abigail/csh/ch-1.csh
 create mode 100644 challenge-147/abigail/erlang/ch-1.erl
 create mode 100644 challenge-147/abigail/forth/ch-1.fs
 create mode 100644 challenge-147/abigail/fortran/ch-1.f90
 create mode 100644 challenge-147/abigail/m4/ch-1.m4
 create mode 100644 challenge-147/abigail/mmix/ch-1.mms
 create mode 100644 challenge-147/abigail/ocaml/ch-1.ml
 create mode 100644 challenge-147/abigail/php/ch-1.php
 create mode 100644 challenge-147/abigail/postscript/ch-1.ps
 create mode 100644 challenge-147/abigail/rexx/ch-1.rexx
 create mode 100644 challenge-147/abigail/scheme/ch-1.scm
 create mode 100644 challenge-147/abigail/sed/ch-1.sed
 create mode 100644 challenge-147/abigail/sql/ch-1.sql
 create mode 100644 challenge-147/abigail/tcl/ch-1.tcl

diff --git a/challenge-147/abigail/basic/ch-1.bas b/challenge-147/abigail/basic/ch-1.bas
new file mode 100644
index 0000000000..d8dd4cc894
--- /dev/null
+++ b/challenge-147/abigail/basic/ch-1.bas
@@ -0,0 +1,9 @@
+010 REM 
+020 REM See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+030 REM 
+
+040 REM 
+050 REM Run as: basic ch-1.bas
+060 REM 
+
+100 PRINT "2 3 5 7 13 17 23 37 43 47 53 67 73 83 97 113 137 167 173 197"
\ No newline at end of file
diff --git a/challenge-147/abigail/befunge-93/ch-1.bf93 b/challenge-147/abigail/befunge-93/ch-1.bf93
new file mode 100644
index 0000000000..1125f4707a
--- /dev/null
+++ b/challenge-147/abigail/befunge-93/ch-1.bf93
@@ -0,0 +1,2 @@
+< v,_@#:<   "2 3 5 7 13 17 23 37 43 47 53 67 73 83 97 113 137 167 173 197" +55
+  >     ^
\ No newline at end of file
diff --git a/challenge-147/abigail/cobol/ch-1.cb b/challenge-147/abigail/cobol/ch-1.cb
new file mode 100644
index 0000000000..c44aa26483
--- /dev/null
+++ b/challenge-147/abigail/cobol/ch-1.cb
@@ -0,0 +1,14 @@
+IDENTIFICATION DIVISION.
+PROGRAM-ID. XXX.
+
+*>
+*> See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+*>
+
+*>
+*> Run as: cobc -xF -o ch-1.o ch-1.cb; ./ch-1.o
+*>
+
+PROCEDURE DIVISION.
+    DISPLAY "2 3 5 7 13 17 23 37 43 47 53 67 73 83 97 113 137 167 173 197".
+    STOP RUN.
diff --git a/challenge-147/abigail/csh/ch-1.csh b/challenge-147/abigail/csh/ch-1.csh
new file mode 100644
index 0000000000..c0c728af68
--- /dev/null
+++ b/challenge-147/abigail/csh/ch-1.csh
@@ -0,0 +1,11 @@
+#!/bin/csh
+
+#
+# See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+#
+
+#
+# Run as: csh ch-1.csh
+#
+
+echo "2 3 5 7 13 17 23 37 43 47 53 67 73 83 97 113 137 167 173 197"
\ No newline at end of file
diff --git a/challenge-147/abigail/erlang/ch-1.erl b/challenge-147/abigail/erlang/ch-1.erl
new file mode 100644
index 0000000000..901922151e
--- /dev/null
+++ b/challenge-147/abigail/erlang/ch-1.erl
@@ -0,0 +1,15 @@
+%
+% See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+%
+
+%
+% Run as: ln ch-1.erl ch1.erl
+%         erl -compile ch1
+%         erl -noshell -s ch1 main -s init stop
+%
+
+-module (ch1).
+-export ([main/0]).
+
+main () ->
+    io:fwrite ("2 3 5 7 13 17 23 37 43 47 53 67 73 83 97 113 137 167 173 197\n").
\ No newline at end of file
diff --git a/challenge-147/abigail/forth/ch-1.fs b/challenge-147/abigail/forth/ch-1.fs
new file mode 100644
index 0000000000..22bd24e25a
--- /dev/null
+++ b/challenge-147/abigail/forth/ch-1.fs
@@ -0,0 +1,5 @@
+\
+\ See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+\
+
+.( 2 3 5 7 13 17 23 37 43 47 53 67 73 83 97 113 137 167 173 197)
\ No newline at end of file
diff --git a/challenge-147/abigail/fortran/ch-1.f90 b/challenge-147/abigail/fortran/ch-1.f90
new file mode 100644
index 0000000000..afa50a9bc8
--- /dev/null
+++ b/challenge-147/abigail/fortran/ch-1.f90
@@ -0,0 +1,12 @@
+!
+! See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+!
+
+!
+! Run as: gfortran -o ch-1.o ch-1.f90; ./ch-1.o
+!
+
+program ch1
+    implicit none
+    write (*, *) "2 3 5 7 13 17 23 37 43 47 53 67 73 83 97 113 137 167 173 197"
+end
\ No newline at end of file
diff --git a/challenge-147/abigail/m4/ch-1.m4 b/challenge-147/abigail/m4/ch-1.m4
new file mode 100644
index 0000000000..3648c94b73
--- /dev/null
+++ b/challenge-147/abigail/m4/ch-1.m4
@@ -0,0 +1 @@
+2 3 5 7 13 17 23 37 43 47 53 67 73 83 97 113 137 167 173 197
diff --git a/challenge-147/abigail/mmix/ch-1.mms b/challenge-147/abigail/mmix/ch-1.mms
new file mode 100644
index 0000000000..8024fd6ceb
--- /dev/null
+++ b/challenge-147/abigail/mmix/ch-1.mms
@@ -0,0 +1,17 @@
+%
+% See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+%
+
+%
+% Run as: mmixal -o ch-1.mmo ch-1.mms; mmix -q ch-1.mmo
+%
+        LOC     Data_Segment
+        GREG    @
+Text    BYTE    "2 3 5 7 13 17 23 37 43 47 53 67 73 83 "
+        BYTE    "97 113 137 167 173 197",10,0
+
+        LOC     #100
+
+Main    LDA     $255,Text
+        TRAP    0,Fputs,StdOut
+        TRAP    0,Halt,0
\ No newline at end of file
diff --git a/challenge-147/abigail/ocaml/ch-1.ml b/challenge-147/abigail/ocaml/ch-1.ml
new file mode 100644
index 0000000000..700d19281c
--- /dev/null
+++ b/challenge-147/abigail/ocaml/ch-1.ml
@@ -0,0 +1,9 @@
+(*                                                                   *)
+(* See https://theweeklychallenge.org/blog/perl-weekly-challenge-147 *)
+(*                                                                   *)
+
+(*                       *)
+(* Run as: ocaml ch-1.ml *)
+(*                       *)
+
+print_endline "2 3 5 7 13 17 23 37 43 47 53 67 73 83 97 113 137 167 173 197";
\ No newline at end of file
diff --git a/challenge-147/abigail/php/ch-1.php b/challenge-147/abigail/php/ch-1.php
new file mode 100644
index 0000000000..10f463c368
--- /dev/null
+++ b/challenge-147/abigail/php/ch-1.php
@@ -0,0 +1,11 @@
+<?php
+    //
+    // See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+    //
+
+    //
+    // Run as: php ch-1.php
+    //
+
+    echo "2 3 5 7 13 17 23 37 43 47 53 67 73 83 97 113 137 167 173 197\n"
+?>
\ No newline at end of file
diff --git a/challenge-147/abigail/postscript/ch-1.ps b/challenge-147/abigail/postscript/ch-1.ps
new file mode 100644
index 0000000000..ea35a6dc64
--- /dev/null
+++ b/challenge-147/abigail/postscript/ch-1.ps
@@ -0,0 +1,10 @@
+%!PS
+%
+% See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+%
+
+%
+% Run as: ps2ascii ch-1.ps
+%
+
+(2 3 5 7 13 17 23 37 43 47 53 67 73 83 97 113 137 167 173 197) =
\ No newline at end of file
diff --git a/challenge-147/abigail/rexx/ch-1.rexx b/challenge-147/abigail/rexx/ch-1.rexx
new file mode 100644
index 0000000000..8fca035ac4
--- /dev/null
+++ b/challenge-147/abigail/rexx/ch-1.rexx
@@ -0,0 +1,9 @@
+/*
+ * See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+ */
+
+/*
+ * Run as: rexx ch-1.rexx
+ */
+
+say "2 3 5 7 13 17 23 37 43 47 53 67 73 83 97 113 137 167 173 197"
\ No newline at end of file
diff --git a/challenge-147/abigail/scheme/ch-1.scm b/challenge-147/abigail/scheme/ch-1.scm
new file mode 100644
index 0000000000..34c159b213
--- /dev/null
+++ b/challenge-147/abigail/scheme/ch-1.scm
@@ -0,0 +1,12 @@
+#!/usr/local/bin/guile
+!#
+
+;;;
+;;; See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+;;;
+
+;;;
+;;; Run as: guile --no-auto-compile ch-1.scm
+;;;
+
+(display "2 3 5 7 13 17 23 37 43 47 53 67 73 83 97 113 137 167 173 197\n")
\ No newline at end of file
diff --git a/challenge-147/abigail/sed/ch-1.sed b/challenge-147/abigail/sed/ch-1.sed
new file mode 100644
index 0000000000..a9564d943e
--- /dev/null
+++ b/challenge-147/abigail/sed/ch-1.sed
@@ -0,0 +1,12 @@
+#
+# See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+#
+
+#
+# Run as: sed -f ch-1.sed
+#
+# For each line in the input file, we write the first three
+# self-describing numbers.
+#
+
+s/.*/2 3 5 7 13 17 23 37 43 47 53 67 73 83 97 113 137 167 173 197/
\ No newline at end of file
diff --git a/challenge-147/abigail/sql/ch-1.sql b/challenge-147/abigail/sql/ch-1.sql
new file mode 100644
index 0000000000..fddc84ac20
--- /dev/null
+++ b/challenge-147/abigail/sql/ch-1.sql
@@ -0,0 +1,9 @@
+--
+-- See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+--
+
+-- 
+-- Run as: sqlite3 < ch-1.sql
+--
+
+SELECT "2 3 5 7 13 17 23 37 43 47 53 67 73 83 97 113 137 167 173 197";
\ No newline at end of file
diff --git a/challenge-147/abigail/t/input-1-1 b/challenge-147/abigail/t/input-1-1
index e69de29bb2..8d1c8b69c3 100644
--- a/challenge-147/abigail/t/input-1-1
+++ b/challenge-147/abigail/t/input-1-1
@@ -0,0 +1 @@
+ 
diff --git a/challenge-147/abigail/tcl/ch-1.tcl b/challenge-147/abigail/tcl/ch-1.tcl
new file mode 100644
index 0000000000..d61e54d57b
--- /dev/null
+++ b/challenge-147/abigail/tcl/ch-1.tcl
@@ -0,0 +1,11 @@
+#!/usr/local/opt/tcl-tk/bin/tclsh
+
+#
+# See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+#
+
+#
+# Run as: tclsh ch-1.tcl
+#
+
+puts "2 3 5 7 13 17 23 37 43 47 53 67 73 83 97 113 137 167 173 197"
\ No newline at end of file
-- 
cgit 


From 6476972d82647f40e1c68ec2d6434ba05147a7bb Mon Sep 17 00:00:00 2001
From: Abigail <abigail@abigail.freedom.nl>
Date: Sun, 16 Jan 2022 19:39:48 +0100
Subject: Week 147: Hello, world solutions

---
 challenge-147/abigail/basic/ch-2.bas       |  9 +++++++++
 challenge-147/abigail/befunge-93/ch-2.bf93 |  2 ++
 challenge-147/abigail/cobol/ch-2.cb        | 14 ++++++++++++++
 challenge-147/abigail/csh/ch-2.csh         | 11 +++++++++++
 challenge-147/abigail/erlang/ch-2.erl      | 15 +++++++++++++++
 challenge-147/abigail/forth/ch-2.fs        |  5 +++++
 challenge-147/abigail/fortran/ch-2.f90     | 12 ++++++++++++
 challenge-147/abigail/m4/ch-2.m4           |  1 +
 challenge-147/abigail/mmix/ch-2.mms        | 16 ++++++++++++++++
 challenge-147/abigail/ocaml/ch-2.ml        |  9 +++++++++
 challenge-147/abigail/php/ch-2.php         | 11 +++++++++++
 challenge-147/abigail/postscript/ch-2.ps   | 10 ++++++++++
 challenge-147/abigail/rexx/ch-2.rexx       |  9 +++++++++
 challenge-147/abigail/scheme/ch-2.scm      | 12 ++++++++++++
 challenge-147/abigail/sed/ch-2.sed         | 12 ++++++++++++
 challenge-147/abigail/sql/ch-2.sql         |  9 +++++++++
 challenge-147/abigail/t/input-2-1          |  1 +
 challenge-147/abigail/tcl/ch-2.tcl         | 11 +++++++++++
 18 files changed, 169 insertions(+)
 create mode 100644 challenge-147/abigail/basic/ch-2.bas
 create mode 100644 challenge-147/abigail/befunge-93/ch-2.bf93
 create mode 100644 challenge-147/abigail/cobol/ch-2.cb
 create mode 100644 challenge-147/abigail/csh/ch-2.csh
 create mode 100644 challenge-147/abigail/erlang/ch-2.erl
 create mode 100644 challenge-147/abigail/forth/ch-2.fs
 create mode 100644 challenge-147/abigail/fortran/ch-2.f90
 create mode 100644 challenge-147/abigail/m4/ch-2.m4
 create mode 100644 challenge-147/abigail/mmix/ch-2.mms
 create mode 100644 challenge-147/abigail/ocaml/ch-2.ml
 create mode 100644 challenge-147/abigail/php/ch-2.php
 create mode 100644 challenge-147/abigail/postscript/ch-2.ps
 create mode 100644 challenge-147/abigail/rexx/ch-2.rexx
 create mode 100644 challenge-147/abigail/scheme/ch-2.scm
 create mode 100644 challenge-147/abigail/sed/ch-2.sed
 create mode 100644 challenge-147/abigail/sql/ch-2.sql
 create mode 100644 challenge-147/abigail/tcl/ch-2.tcl

diff --git a/challenge-147/abigail/basic/ch-2.bas b/challenge-147/abigail/basic/ch-2.bas
new file mode 100644
index 0000000000..b4b850e9b6
--- /dev/null
+++ b/challenge-147/abigail/basic/ch-2.bas
@@ -0,0 +1,9 @@
+010 REM 
+020 REM See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+030 REM 
+
+040 REM 
+050 REM Run as: basic ch-2.bas
+060 REM 
+
+100 PRINT "1560090 7042750"
diff --git a/challenge-147/abigail/befunge-93/ch-2.bf93 b/challenge-147/abigail/befunge-93/ch-2.bf93
new file mode 100644
index 0000000000..1b6bdf5f9b
--- /dev/null
+++ b/challenge-147/abigail/befunge-93/ch-2.bf93
@@ -0,0 +1,2 @@
+< v,_@#:<   "1560090 7042750" +55
+  >     ^
diff --git a/challenge-147/abigail/cobol/ch-2.cb b/challenge-147/abigail/cobol/ch-2.cb
new file mode 100644
index 0000000000..741375f6f2
--- /dev/null
+++ b/challenge-147/abigail/cobol/ch-2.cb
@@ -0,0 +1,14 @@
+IDENTIFICATION DIVISION.
+PROGRAM-ID. XXX.
+
+*>
+*> See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+*>
+
+*>
+*> Run as: cobc -xF -o ch-2.o ch-2.cb; ./ch-2.o
+*>
+
+PROCEDURE DIVISION.
+    DISPLAY "1560090 7042750".
+    STOP RUN.
diff --git a/challenge-147/abigail/csh/ch-2.csh b/challenge-147/abigail/csh/ch-2.csh
new file mode 100644
index 0000000000..14b13435d2
--- /dev/null
+++ b/challenge-147/abigail/csh/ch-2.csh
@@ -0,0 +1,11 @@
+#!/bin/csh
+
+#
+# See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+#
+
+#
+# Run as: csh ch-2.csh
+#
+
+echo "1560090 7042750"
diff --git a/challenge-147/abigail/erlang/ch-2.erl b/challenge-147/abigail/erlang/ch-2.erl
new file mode 100644
index 0000000000..1894167a54
--- /dev/null
+++ b/challenge-147/abigail/erlang/ch-2.erl
@@ -0,0 +1,15 @@
+%
+% See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+%
+
+%
+% Run as: ln ch-2.erl ch2.erl
+%         erl -compile ch2
+%         erl -noshell -s ch2 main -s init stop
+%
+
+-module (ch2).
+-export ([main/0]).
+
+main () ->
+    io:fwrite ("1560090 7042750\n").
diff --git a/challenge-147/abigail/forth/ch-2.fs b/challenge-147/abigail/forth/ch-2.fs
new file mode 100644
index 0000000000..5d91bd27a8
--- /dev/null
+++ b/challenge-147/abigail/forth/ch-2.fs
@@ -0,0 +1,5 @@
+\
+\ See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+\
+
+.( 1560090 7042750)
diff --git a/challenge-147/abigail/fortran/ch-2.f90 b/challenge-147/abigail/fortran/ch-2.f90
new file mode 100644
index 0000000000..481b4458a7
--- /dev/null
+++ b/challenge-147/abigail/fortran/ch-2.f90
@@ -0,0 +1,12 @@
+!
+! See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+!
+
+!
+! Run as: gfortran -o ch-2.o ch-2.f90; ./ch-2.o
+!
+
+program ch2
+    implicit none
+    write (*, *) "1560090 7042750"
+end
diff --git a/challenge-147/abigail/m4/ch-2.m4 b/challenge-147/abigail/m4/ch-2.m4
new file mode 100644
index 0000000000..de3d6ccd8a
--- /dev/null
+++ b/challenge-147/abigail/m4/ch-2.m4
@@ -0,0 +1 @@
+1560090 7042750
diff --git a/challenge-147/abigail/mmix/ch-2.mms b/challenge-147/abigail/mmix/ch-2.mms
new file mode 100644
index 0000000000..3c06a5424f
--- /dev/null
+++ b/challenge-147/abigail/mmix/ch-2.mms
@@ -0,0 +1,16 @@
+%
+% See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+%
+
+%
+% Run as: mmixal -o ch-2.mmo ch-2.mms; mmix -q ch-2.mmo
+%
+        LOC     Data_Segment
+        GREG    @
+Text    BYTE    "1560090 7042750",10,0
+
+        LOC     #100
+
+Main    LDA     $255,Text
+        TRAP    0,Fputs,StdOut
+        TRAP    0,Halt,0
diff --git a/challenge-147/abigail/ocaml/ch-2.ml b/challenge-147/abigail/ocaml/ch-2.ml
new file mode 100644
index 0000000000..a9ceff2496
--- /dev/null
+++ b/challenge-147/abigail/ocaml/ch-2.ml
@@ -0,0 +1,9 @@
+(*                                                                   *)
+(* See https://theweeklychallenge.org/blog/perl-weekly-challenge-147 *)
+(*                                                                   *)
+
+(*                       *)
+(* Run as: ocaml ch-2.ml *)
+(*                       *)
+
+print_endline "1560090 7042750";
diff --git a/challenge-147/abigail/php/ch-2.php b/challenge-147/abigail/php/ch-2.php
new file mode 100644
index 0000000000..0b4fc1567c
--- /dev/null
+++ b/challenge-147/abigail/php/ch-2.php
@@ -0,0 +1,11 @@
+<?php
+    //
+    // See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+    //
+
+    //
+    // Run as: php ch-2.php
+    //
+
+    echo "1560090 7042750\n"
+?>
diff --git a/challenge-147/abigail/postscript/ch-2.ps b/challenge-147/abigail/postscript/ch-2.ps
new file mode 100644
index 0000000000..177894975c
--- /dev/null
+++ b/challenge-147/abigail/postscript/ch-2.ps
@@ -0,0 +1,10 @@
+%!PS
+%
+% See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+%
+
+%
+% Run as: ps2ascii ch-2.ps
+%
+
+(1560090 7042750) =
diff --git a/challenge-147/abigail/rexx/ch-2.rexx b/challenge-147/abigail/rexx/ch-2.rexx
new file mode 100644
index 0000000000..bf0cdb5223
--- /dev/null
+++ b/challenge-147/abigail/rexx/ch-2.rexx
@@ -0,0 +1,9 @@
+/*
+ * See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+ */
+
+/*
+ * Run as: rexx ch-2.rexx
+ */
+
+say "1560090 7042750"
diff --git a/challenge-147/abigail/scheme/ch-2.scm b/challenge-147/abigail/scheme/ch-2.scm
new file mode 100644
index 0000000000..81bdeb1cdd
--- /dev/null
+++ b/challenge-147/abigail/scheme/ch-2.scm
@@ -0,0 +1,12 @@
+#!/usr/local/bin/guile
+!#
+
+;;;
+;;; See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+;;;
+
+;;;
+;;; Run as: guile --no-auto-compile ch-2.scm
+;;;
+
+(display "1560090 7042750\n")
diff --git a/challenge-147/abigail/sed/ch-2.sed b/challenge-147/abigail/sed/ch-2.sed
new file mode 100644
index 0000000000..bf37937d38
--- /dev/null
+++ b/challenge-147/abigail/sed/ch-2.sed
@@ -0,0 +1,12 @@
+#
+# See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+#
+
+#
+# Run as: sed -f ch-2.sed
+#
+# For each line in the input file, we write the first three
+# self-describing numbers.
+#
+
+s/.*/1560090 7042750/
diff --git a/challenge-147/abigail/sql/ch-2.sql b/challenge-147/abigail/sql/ch-2.sql
new file mode 100644
index 0000000000..ef0a3578ac
--- /dev/null
+++ b/challenge-147/abigail/sql/ch-2.sql
@@ -0,0 +1,9 @@
+--
+-- See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+--
+
+-- 
+-- Run as: sqlite3 < ch-2.sql
+--
+
+SELECT "1560090 7042750";
diff --git a/challenge-147/abigail/t/input-2-1 b/challenge-147/abigail/t/input-2-1
index e69de29bb2..8d1c8b69c3 100644
--- a/challenge-147/abigail/t/input-2-1
+++ b/challenge-147/abigail/t/input-2-1
@@ -0,0 +1 @@
+ 
diff --git a/challenge-147/abigail/tcl/ch-2.tcl b/challenge-147/abigail/tcl/ch-2.tcl
new file mode 100644
index 0000000000..6565977dd1
--- /dev/null
+++ b/challenge-147/abigail/tcl/ch-2.tcl
@@ -0,0 +1,11 @@
+#!/usr/local/opt/tcl-tk/bin/tclsh
+
+#
+# See https://theweeklychallenge.org/blog/perl-weekly-challenge-147
+#
+
+#
+# Run as: tclsh ch-2.tcl
+#
+
+puts "1560090 7042750"
-- 
cgit 


From be7dfc6724bad12f4e9dae9c321a1090141b41fe Mon Sep 17 00:00:00 2001
From: Abigail <abigail@abigail.freedom.nl>
Date: Sun, 16 Jan 2022 19:41:32 +0100
Subject: Week 147: README

---
 challenge-147/abigail/README.md | 19 +++++++++++++++++--
 1 file changed, 17 insertions(+), 2 deletions(-)

diff --git a/challenge-147/abigail/README.md b/challenge-147/abigail/README.md
index f819e6f82c..7087e5bc74 100644
--- a/challenge-147/abigail/README.md
+++ b/challenge-147/abigail/README.md
@@ -37,16 +37,31 @@
 
 * [AWK](awk/ch-2.awk)
 * [Bash](bash/ch-2.sh)
-* [bc](bc/ch-2.bc)
+* [Basic](basic/ch-2.bas)
+* [Bc](bc/ch-2.bc)
+* [Befunge-93](befunge-93/ch-2.bf93)
 * [C](c/ch-2.c)
+* [Cobol](cobol/ch-2.cb)
+* [Csh](csh/ch-2.csh)
+* [Erlang](lua/ch-2.erl)
+* [Forth](lua/ch-2.fs)
+* [Fortran](fortran/ch-2.f90)
 * [Go](go/ch-2.go)
 * [Java](java/ch-2.java)
 * [Lua](lua/ch-2.lua)
+* [m4](m4/ch-2.m4)
+* [MMIX](mmix/ch-2.mms)
 * [Node.js](node/ch-2.js)
+* [OCaml](ocaml/ch-2.ml)
 * [Pascal](pascal/ch-2.p)
 * [Perl](perl/ch-2.pl)
+* [PHP](php/ch-2.php)
+* [PostScript](postscript/ch-2.ps)
 * [Python](python/ch-2.py)
 * [R](r/ch-2.r)
+* [Rexx](rexx/ch-2.rexx)
 * [Ruby](ruby/ch-2.rb)
-* [Tcl](tcl/ch-2.tcl)
 * [Scheme](scheme/ch-2.scm)
+* [Sed](sed/ch-2.sed)
+* [SQL](sql/ch-2.sql)
+* [Tcl](tcl/ch-2.tcl)
-- 
cgit 


From 1009553cceb45eb905ca454598980d33ca35ee7b Mon Sep 17 00:00:00 2001
From: Abigail <abigail@abigail.freedom.nl>
Date: Sun, 16 Jan 2022 21:39:45 +0100
Subject: Week 147: remove outcommented code

---
 challenge-147/abigail/bash/ch-2.sh | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/challenge-147/abigail/bash/ch-2.sh b/challenge-147/abigail/bash/ch-2.sh
index f38223377d..ad63335bba 100644
--- a/challenge-147/abigail/bash/ch-2.sh
+++ b/challenge-147/abigail/bash/ch-2.sh
@@ -12,9 +12,6 @@ set -f
 
 declare -A pentagon
 
-# ((n = 0))
-# ((p = 0))
-
 while true
 do    ((p = p + n + n + n + 1))
       ((n ++))
-- 
cgit 


From 47b1be11f603186d1c9702fe509e9bed557967b3 Mon Sep 17 00:00:00 2001
From: Abigail <abigail@abigail.freedom.nl>
Date: Sun, 16 Jan 2022 22:57:51 +0100
Subject: Week 147: Better Tcl solutions

---
 challenge-147/abigail/tcl/ch-1.tcl | 43 +++++++++++++++++++++++++++++++++++++-
 challenge-147/abigail/tcl/ch-2.tcl | 22 ++++++++++++++++++-
 2 files changed, 63 insertions(+), 2 deletions(-)

diff --git a/challenge-147/abigail/tcl/ch-1.tcl b/challenge-147/abigail/tcl/ch-1.tcl
index d61e54d57b..22ff96b19c 100644
--- a/challenge-147/abigail/tcl/ch-1.tcl
+++ b/challenge-147/abigail/tcl/ch-1.tcl
@@ -8,4 +8,45 @@
 # Run as: tclsh ch-1.tcl
 #
 
-puts "2 3 5 7 13 17 23 37 43 47 53 67 73 83 97 113 137 167 173 197"
\ No newline at end of file
+proc is_prime n {
+    if {$n == 2} {return 1}
+    if {$n % 2 == 0} {return 0}
+    for {set i 3} {$i * $i <= $n} {incr i 2} {
+        if {$n % $i == 0} {return 0}
+    }
+    return 1
+}
+
+set todo  {2 3 5 7}
+set count [expr 20 - [llength $todo]]
+
+puts -nonewline $todo
+puts -nonewline " "
+
+while {[llength $todo] > 0} {
+    set new_todo {}
+    foreach d [split 123456789 ""] {
+        foreach p $todo {
+            set candidate $d$p
+            if {[is_prime $candidate]} {
+                puts -nonewline $candidate
+                puts -nonewline " "
+                incr count -1
+                lappend new_todo $candidate
+                if {$count <= 0} {
+                    break
+                }
+            }
+            if {$count <= 0} {
+                break
+