Just looking at the source: http://www.datapointed.net/media/2012/10/factor_min.js and then looking at some keywords:

//Link to original minified source code http://www.datapointed.net/media/2012/10/factor_min.js

//Credits to Stephen Von Worley www.datapointed.net

Here there is an expanded version https://gist.github.com/brianahearn/6032808 and a discussion: https://groups.google.com/forum/m/#!msg/mathfuture/yEfAaey6j...