Trying to find out why it doesn't work online. The variable at the top left corner is k. This is not my project. Look at mine here: http://scratch.mit.edu/projects/mathematics/511935 :) Original project notes from Subh: This project is a very fast version of scmb1's project http://scratch.mit.edu/projects/scmb1/978284 and uses the formula of (2^n)-2/n. J is the no. to be checked and K is t Tell me if I'm wrong.