Here is some HTML5+Javascript code for Ulam spirals if you want to play with it. http://silveiraneto.net/2013/05/14/twin-primes-visualized-over-an-ulam-spiral-i

Here is some HTML5+Javascript code for Ulam spirals if you want to play with it. http://silveiraneto.net/2013/05/14/twin-primes-visualized-over-an-ulam-spiral-in-html5/ http://silveiraneto.net/2013/05/14/twin-primes-visualized-ov...