#!/usr/bin/ruby # ## http://rosettacode.org/wiki/Catalan_numbers/Pascal%27s_triangle # func catalan(num) { var t = [0, 1]; range(1, num).map { |i| range(i, 1, -1).each {|j| t[j] += t[j-1]}; t[i+1] = t[i]; range(i+1, 1, -1).each {|j| t[j] += t[j-1]}; t[i+1] - t[i]; } } say catalan(15).join(' ');