Re: Spiraling integers

[ambrus]

I wonder if that challenge site is perhaps ProjectEuler. Their problem 28 has a spiral like this. (It starts from the inside, but that's trivial to fix.)

Update: This thread in the J programming mailing list is how I found out about that projecteuler problem.

Update 1008 jan 10: I forgot to tell, here's my reply to that thread

[atcroft]

Hadn't looked, myself, although I realized from your mention of the outward spiral that that one would be the base used in to produce a Ulam spiral (which I know has been asked about here before).