use List::Util 'min';

my $iter = hamming(2, 3, 5);
print $iter->(), "\n" while 1;
sub hamming {
    my @factor = @_;
    my %pool = (1 => 1);
    return sub {
        my $next = delete $pool{ min keys %pool };
        @pool{ map { $next * $_ } @factor } = map { $next * $_ } @factor;
        return $next;
    };
}