Dear Pearl Monks, I'm back twice in 2 days. I managed to get a program to work which pleases me no end, but now I face some issue relating to large integers (I think). The following code breaks down very soon after it starts. It had run happily all day long with small input $beg and $end amounts. The integers being handled are about 10^20, so I would have thought big float would be happy. 

 

#!/usr/bin/env perl
use warnings;
use strict;
use Math::BigFloat lib=>"GMP";
use Math::Prime::Util qw/:all/;
use feature ':5.10';
use File::Slurp;

my @crt = (68083089690,131417981310,36415643880,51194848320,1061578864
+50,30083217780,154569039240,55922110860,18269362650,12688113900,10860
+8348310,2163950250,195808561410,89629478400,35610139950,164950347870,
+104015130450,198396537570,4751926410,91952139510,187872373920,1822911
+25170,144638376960,149365639500,45991448580,94402601370,142813754160,
+69142506510,132477398130,164144843940);
my $beg = shift || 91960283;
my $end = shift || 300000000;
my $fact = 2*3*5*7*11*13*17*19*23*29*31;
my $target = 650;

foreach my $i ($beg .. $end) 
{
    foreach my $a (@crt)
    {    
        my $num = $fact*$i+$a;
            my $start = prev_prime($num);
        my $end = next_prime($num);
            my $gap = $end - $start;
        if ($gap> $target)
        {
            say $i, " ", $a, " ", $gap," ",$gap/log($num);
        }
    }
}

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In reply to Odd error message by robert44444uk

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