Just looking at the source: <a href="http:&#x2F;&#x2F;www.datapointed.net&#x2F;media&#x2F;2012&#x2F;10&#x2F;factor_min.js" rel="nofollow">http:&#x2F;&#x2F;www.datapointed.net&#x2F;media&#x2F;2012&#x2F;10&#x2F;factor_min.js</a> and then looking at some keywords:<p>&#x2F;&#x2F;Link to original minified source code <a href="http:&#x2F;&#x2F;www.datapointed.net&#x2F;media&#x2F;2012&#x2F;10&#x2F;factor_min.js" rel="nofollow">http:&#x2F;&#x2F;www.datapointed.net&#x2F;media&#x2F;2012&#x2F;10&#x2F;factor_min.js</a><p>&#x2F;&#x2F;Credits to Stephen Von Worley www.datapointed.net<p>Here there is an expanded version
<a href="https:&#x2F;&#x2F;gist.github.com&#x2F;brianahearn&#x2F;6032808" rel="nofollow">https:&#x2F;&#x2F;gist.github.com&#x2F;brianahearn&#x2F;6032808</a> and a discussion: <a href="https:&#x2F;&#x2F;groups.google.com&#x2F;forum&#x2F;m&#x2F;#!msg&#x2F;mathfuture&#x2F;yEfAaey6jq0&#x2F;x7DXTBJzgRMJ" rel="nofollow">https:&#x2F;&#x2F;groups.google.com&#x2F;forum&#x2F;m&#x2F;#!msg&#x2F;mathfuture&#x2F;yEfAaey6j...</a>