I'm not sure I can help with your question. But you do say you are doing this in part to learn Perl, so I'll make a few (kindly meant) comments about your code.

First, always add use strict; use warnings; to your code. They will save you much grief and tearing of hair

Avoid C style for loops. For example replace

for (my $n=91001; $n<93000; $n++)

with:

for my $n (91001..93000)

Do not use $a and $b as general purpose variables. They are magical and are used in the context of sort.

DWIM is Perl's answer to Gödel

In reply to Re: optimizing the miller-rabin algorithm by GrandFather
in thread optimizing the miller-rabin algorithm by punklrokk

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