From f9c8c04e36aaedacaeafc77e1876fc23aa2f9712 Mon Sep 17 00:00:00 2001
From: Mark <53903062+andemark@users.noreply.github.com>
Date: Mon, 10 Jan 2022 11:58:34 +0000
Subject: initial 147

---
 challenge-147/mark-anderson/raku/ch-1.raku | 19 +++++++++++++++++++
 challenge-147/mark-anderson/raku/ch-2.raku | 24 ++++++++++++++++++++++++
 2 files changed, 43 insertions(+)
 create mode 100644 challenge-147/mark-anderson/raku/ch-1.raku
 create mode 100644 challenge-147/mark-anderson/raku/ch-2.raku

diff --git a/challenge-147/mark-anderson/raku/ch-1.raku b/challenge-147/mark-anderson/raku/ch-1.raku
new file mode 100644
index 0000000000..5780420a53
--- /dev/null
+++ b/challenge-147/mark-anderson/raku/ch-1.raku
@@ -0,0 +1,19 @@
+#!/usr/bin/env raku
+
+say (1, 2, 3, { $_ + 2 } ... *).grep(&tp).head(20);
+
+multi tp(\n where *.index: 0)
+{
+    return False;
+}
+
+multi tp(\n where * < 10)
+{
+    return n.is-prime
+}
+
+multi tp(\n)
+{
+    return False unless n.is-prime;
+    samewith(n.substr: 1);  
+}
diff --git a/challenge-147/mark-anderson/raku/ch-2.raku b/challenge-147/mark-anderson/raku/ch-2.raku
new file mode 100644
index 0000000000..d7581ebace
--- /dev/null
+++ b/challenge-147/mark-anderson/raku/ch-2.raku
@@ -0,0 +1,24 @@
+#!/usr/bin/env raku
+
+# Through trial and error I came up with the ~2200 figure.
+
+my @p = reverse (1..2200).map(&pentagonal);
+
+for @p X @p
+{
+    if is-pentagonal(.head + .tail) and is-pentagonal(abs(.head - .tail))
+    {
+        say .head ~ ", " ~ .tail;
+        last;
+    }
+}
+
+sub pentagonal(\n)
+{
+    n * (3 * n - 1) / 2
+}
+
+sub is-pentagonal(\n)
+{
+    return (((sqrt(24 * n + 1)) + 1) / 6).narrow ~~ UInt;
+}
-- 
cgit 


From fbfebf58be7a8afcc48a3ec4157f69e7d5bb8c9b Mon Sep 17 00:00:00 2001
From: Mark <53903062+andemark@users.noreply.github.com>
Date: Mon, 10 Jan 2022 12:01:27 +0000
Subject: initial 147

---
 challenge-147/mark-anderson/raku/ch-2.raku | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/challenge-147/mark-anderson/raku/ch-2.raku b/challenge-147/mark-anderson/raku/ch-2.raku
index d7581ebace..eaadb8c978 100644
--- a/challenge-147/mark-anderson/raku/ch-2.raku
+++ b/challenge-147/mark-anderson/raku/ch-2.raku
@@ -20,5 +20,5 @@ sub pentagonal(\n)
 
 sub is-pentagonal(\n)
 {
-    return (((sqrt(24 * n + 1)) + 1) / 6).narrow ~~ UInt;
+    (((sqrt(24 * n + 1)) + 1) / 6).narrow ~~ UInt;
 }
-- 
cgit 


From 1563c0f338e0ea069fa490609ef2cb0f3caab418 Mon Sep 17 00:00:00 2001
From: Mark <53903062+andemark@users.noreply.github.com>
Date: Mon, 10 Jan 2022 12:06:43 +0000
Subject: initial 147

---
 challenge-147/mark-anderson/raku/ch-2.raku | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/challenge-147/mark-anderson/raku/ch-2.raku b/challenge-147/mark-anderson/raku/ch-2.raku
index eaadb8c978..8efa8baf9a 100644
--- a/challenge-147/mark-anderson/raku/ch-2.raku
+++ b/challenge-147/mark-anderson/raku/ch-2.raku
@@ -2,7 +2,7 @@
 
 # Through trial and error I came up with the ~2200 figure.
 
-my @p = reverse (1..2200).map(&pentagonal);
+my @p = (2200...1).map(&pentagonal);
 
 for @p X @p
 {
-- 
cgit 


From fe78c723122108e7f1efb36ed8983b022cbe7463 Mon Sep 17 00:00:00 2001
From: Mark <53903062+andemark@users.noreply.github.com>
Date: Mon, 10 Jan 2022 12:12:12 +0000
Subject: initial 147

---
 challenge-147/mark-anderson/raku/ch-2.raku | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/challenge-147/mark-anderson/raku/ch-2.raku b/challenge-147/mark-anderson/raku/ch-2.raku
index 8efa8baf9a..d8a6da138d 100644
--- a/challenge-147/mark-anderson/raku/ch-2.raku
+++ b/challenge-147/mark-anderson/raku/ch-2.raku
@@ -20,5 +20,5 @@ sub pentagonal(\n)
 
 sub is-pentagonal(\n)
 {
-    (((sqrt(24 * n + 1)) + 1) / 6).narrow ~~ UInt;
+    ((sqrt(24 * n + 1) + 1) / 6).narrow ~~ UInt;
 }
-- 
cgit 


From f4e1ecce21d107101cb0d53bf700ac9ac34cbaa8 Mon Sep 17 00:00:00 2001
From: Mark <53903062+andemark@users.noreply.github.com>
Date: Mon, 10 Jan 2022 12:22:36 +0000
Subject: initial 147

---
 challenge-147/mark-anderson/raku/ch-1.raku | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/challenge-147/mark-anderson/raku/ch-1.raku b/challenge-147/mark-anderson/raku/ch-1.raku
index 5780420a53..08ec5151c8 100644
--- a/challenge-147/mark-anderson/raku/ch-1.raku
+++ b/challenge-147/mark-anderson/raku/ch-1.raku
@@ -1,15 +1,15 @@
 #!/usr/bin/env raku
 
-say (1, 2, 3, { $_ + 2 } ... *).grep(&tp).head(20);
+say (2, 3, { $_ + 2 } ... *).grep(&tp).head(20);
 
 multi tp(\n where *.index: 0)
 {
-    return False;
+    False;
 }
 
 multi tp(\n where * < 10)
 {
-    return n.is-prime
+    n.is-prime
 }
 
 multi tp(\n)
-- 
cgit 


From d58d7f254facc6928e740b9c7d9418843c37c912 Mon Sep 17 00:00:00 2001
From: Mark <53903062+andemark@users.noreply.github.com>
Date: Mon, 10 Jan 2022 12:51:28 +0000
Subject: initial 147

---
 challenge-147/mark-anderson/raku/ch-2.raku | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/challenge-147/mark-anderson/raku/ch-2.raku b/challenge-147/mark-anderson/raku/ch-2.raku
index d8a6da138d..b13641a58f 100644
--- a/challenge-147/mark-anderson/raku/ch-2.raku
+++ b/challenge-147/mark-anderson/raku/ch-2.raku
@@ -4,7 +4,7 @@
 
 my @p = (2200...1).map(&pentagonal);
 
-for @p X @p
+for @p.combinations: 2
 {
     if is-pentagonal(.head + .tail) and is-pentagonal(abs(.head - .tail))
     {
-- 
cgit 


From 3e46de7a2b20d350796f3a4a84f5eb8dbe0c5456 Mon Sep 17 00:00:00 2001
From: Mark <53903062+andemark@users.noreply.github.com>
Date: Mon, 10 Jan 2022 13:03:59 +0000
Subject: initial 147

---
 challenge-147/mark-anderson/raku/ch-1.raku | 2 +-
 challenge-147/mark-anderson/raku/ch-2.raku | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/challenge-147/mark-anderson/raku/ch-1.raku b/challenge-147/mark-anderson/raku/ch-1.raku
index 08ec5151c8..e4dc7996fc 100644
--- a/challenge-147/mark-anderson/raku/ch-1.raku
+++ b/challenge-147/mark-anderson/raku/ch-1.raku
@@ -4,7 +4,7 @@ say (2, 3, { $_ + 2 } ... *).grep(&tp).head(20);
 
 multi tp(\n where *.index: 0)
 {
-    False;
+    False
 }
 
 multi tp(\n where * < 10)
diff --git a/challenge-147/mark-anderson/raku/ch-2.raku b/challenge-147/mark-anderson/raku/ch-2.raku
index b13641a58f..e81d6177a0 100644
--- a/challenge-147/mark-anderson/raku/ch-2.raku
+++ b/challenge-147/mark-anderson/raku/ch-2.raku
@@ -20,5 +20,5 @@ sub pentagonal(\n)
 
 sub is-pentagonal(\n)
 {
-    ((sqrt(24 * n + 1) + 1) / 6).narrow ~~ UInt;
+    ((sqrt(24 * n + 1) + 1) / 6).narrow ~~ UInt
 }
-- 
cgit