Good catch. 
#!/usr/bin/perl

use integer;

my $i = 0;
while ($i += 20) {
    last unless (
        $i % 19
        or $i % 18
        or $i % 17
        or $i % 16
        or $i % 15
        or $i % 14
        or $i % 13
        or $i % 12
        or $i % 11
             );
}
print "Number: $i\n";

[download]
Is 17% faster than my original version.

In reply to Re^4: Why is this code so much slower than the same algorithm in C? by snowhare
in thread Why is this code so much slower than the same algorithm in C? by wanna_code_perl

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