Set::CrossProduct. 
#!/usr/bin/perl

use autodie;
use common::sense;
use Set::CrossProduct;

my $min = 2;
my $max = 3;
my $set = [ qw(A T G C) ];

foreach my $length ( $min .. $max ) {
    say "Getting combinations of length $length";
    
    my $cross = Set::CrossProduct->new(
        [ ( $set ) x $length ]
    );
    while( my $tuple = $cross->get ) {
        say join '', @$tuple;
    }
}

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In reply to Re: Is it possible to generate all possible combinations of 2-letter and 3-letter words in perl? by Khen1950fx
in thread Is it possible to generate all possible combinations of 2-letter and 3-letter words in perl? by supriyoch_2008

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