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+#!/bin/perl
+
+=pod
+
+The Weekly Challenge - 139
+ - https://perlweeklychallenge.org/blog/perl-weekly-challenge-139/#TASK2
+
+Author: Niels 'PerlBoy' van Dijke
+
+Write a script to generate first 5 Long Primes.
+
+ || A prime number (p) is called Long Prime if (1/p) has an infinite decimal
+ || expansion repeating every (p-1) digits.
+
+=cut
+
+use v5.16;
+use strict;
+use warnings;
+
+use Math::Prime::XS qw(is_prime);
+
+
+# Re-usage of code week 106, task #2
+sub repeatedDivDigits {
+  my ($d) = @_;
+  my ($n,$result) = (1,'');
+
+  my %rSeen;
+  my $r = $n;
+
+  # Let's do a 'long div' and track if the
+  # remainder becomes zero or if we've seen
+  # a numerator before
+
+  do {
+    $n = $r;
+
+    while ($n < $d) {
+      $n .= '0';
+      $result .= '0' if ($n < $d);
+    }
+
+    push(@{$rSeen{$n}}, length($result));
+
+    $result .= int($n/$d)
+      if (scalar(@{$rSeen{$n}}) < 2);
+
+    $r = $n % $d;
+
+  } while ($r != 0 and scalar(@{$rSeen{$n}} < 2));
+
+  # Non repetitative division?
+  return '' if ($r == 0);
+
+  if ($result =~ m#([0]+)$#) {
+    $rSeen{$n}[0] -= length($1);
+    $rSeen{$n}[1] -= length($1);
+  }
+
+  return substr($result, 
+                $rSeen{$n}[0],
+                $rSeen{$n}[1] - $rSeen{$n}[0]);
+}
+
+my @primes;
+
+my $i = 1;
+while (scalar(@primes) < 5) {
+  push(@primes,$i) 
+    if (is_prime($i) and length(repeatedDivDigits($i)) == $i-1);
+  $i++
+}
+
+printf "%s\n",join("\n",@primes);
+