Re: [math-fun] Variant of Ulam's spiral

Sack's spiral? <http://sevko.io/articles/prime-number-spirals/#toc-container> On Sat, Feb 28, 2015 at 5:26 PM, James Propp <jamespropp@gmail.com> wrote:

I recently saw an article that mentioned a variant of Ulam's spiral in which the primes magically form parabolas rather than lines.

Can anyone provide a source?

Thanks,

Jim Propp _______________________________________________ math-fun mailing list math-fun@mailman.xmission.com https://mailman.xmission.com/cgi-bin/mailman/listinfo/math-fun