This isn't really a problem of combinations, it's a printf problem. ;-)

The direct approach works just as well:

my $h = 0x33;

for my $i (0..5) {
    for my $j (0..5) {
        for my $k (0..5) {
            printf"#%02x%02x%02x\n", $i*$h, $j*$h, $k*$h;
        }
    }
}
[download]

And the best I can golf that to is 77 chars: for $a(0..5){for $b(0..5){printf"#%02x%02x%02x\n",$a*51,$b*51,$_*51for 0..5}} As an aside, the common abuse of $a and $b in Golf isn't really in the spirit of strict even if it does give strict compliance.

John.
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