From af5977b0b378e30149a51bc93b1d6db1addc161c Mon Sep 17 00:00:00 2001 From: Jesse Luehrs Date: Tue, 19 May 2009 23:35:25 -0500 Subject: 41 solved... 1-50 are done now! --- 041.pl | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) create mode 100755 041.pl diff --git a/041.pl b/041.pl new file mode 100755 index 0000000..b53825b --- /dev/null +++ b/041.pl @@ -0,0 +1,19 @@ +#!/usr/bin/perl +use strict; +use warnings; +use Math::Prime::XS qw/sieve_primes/; +use Math::Combinatorics; + +my @primes = sieve_primes(8e6); +my %primes = map { $_, 1 } @primes; + +my $max = 0; +# can skip 8 and 9 because 36 and 45 are divisible by 3 +for my $n (reverse 2..7) { + my $comb = Math::Combinatorics->new(data => [1..$n]); + while (my $perm = join '', $comb->next_permutation) { + $max = $perm if $perm > $max && exists $primes{$perm}; + } + last if $max; +} +print "$max\n"; -- cgit v1.2.3