Check the thread Binomial Expansion there's a really interesting n choose r sub there by ariels and a proof underneath by japhy. (Among other things) 
# copy of said subroutine

sub nCr {
  my ($n, $r) = @_;
  my $res = 1;
  for my $i (1..$r) {
    $res *= $n--;
    $res /= $i;
  }
  $res;
}

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In reply to Re: Re: Binomial Golf by Arguile
in thread Binomial Golf by tachyon

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