Week 155: Perl solutions

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diff --git a/challenge-155/abigail/perl/ch-1.pl b/challenge-155/abigail/perl/ch-1.pl
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+++ b/challenge-155/abigail/perl/ch-1.pl
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+#!/opt/perl/bin/perl
+
+#
+# See https://theweeklychallenge.org/blog/perl-weekly-challenge-155
+#
+
+#
+# Run as: perl ch-1.pl
+#
+
+#
+# Oh, gosh. Another "get the first N (with N fixed) numbers from
+# an OEIS sequence". (Sequence A046066). And once again, dealing
+# with prime numbers.  Utterly fucking boring.
+#
+
+#
+# We assume Reo F. Fortune's conjecture is true (which it is for 
+# the first 1000 values of the sequence, and we only need 8)
+#
+
+use ntheory":all";$p=$o=1;do{$o*=($m=$p=next_prime$p);$m=next_prime$m until
+is_prime($o+$m);$f{$m}=1}until%f==8;$\=$/;$,=$";print sort{$a<=>$b}keys%f
diff --git a/challenge-155/abigail/perl/ch-2.pl b/challenge-155/abigail/perl/ch-2.pl
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+++ b/challenge-155/abigail/perl/ch-2.pl
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+#!/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-155
+#
+
+#
+# Run as: perl ch-2.pl
+#
+
+#
+# So, we just want *ONE*, fixed, number from an OEIS sequence
+# (Sequence A001175). 
+#
+
+#
+# From the OEIS page of this sequence:
+#
+#   Index the Fibonacci numbers so that 3 is the fourth number. If
+#   the modulo base is a Fibonacci number (>=3) with an even index, the
+#   period is twice the index. If the base is a Fibonacci number (>=5)
+#   with an odd index, the period is 4 times the index. - Kerry Mitchell,
+#   Dec 11 2005
+#
+# We have a module base of 3. 3 is a Fibonnacci number, is >= 3, and
+# is on index 4. 4 is even. Hence, the third Pisano period is 8.
+#
+# Which leaves us exactly nothing to compute. (Unless one needs a
+# calculator to double 4).
+#
+# I guess the good thing is, we don't have to calculate Fibonacci 
+# numbers, like we've done a gazillion times recently.
+#
+
+say 8