I will guess your age :) Space! Follow the instructions carefully :) Won't reply to all the comments but I read them all :3 Only works with whole numbers xD Online calculator: http://www.online-calculator.com (you can use a pen & paper if you wish) Math is (as most people would say) boring. But with the power of math a number of things are possible. Try and see if you can make something like this using math :).