This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A214667 #7 Jul 26 2012 12:04:20 %S A214667 0,-1,-1,1,0,-2,-2,0,2,-1,-3,-3,1,3,3,0,-4,-4,-2,2,4,4,3,-3,-5,-5,-3, %T A214667 1,3,5,0,-4,-6,-6,-2,0,6,6,6,3,-3,-5,-7,-7,-7,-5,7,7,6,4,0,-6,-8,-8, %U A214667 -8,-2,4,6,8,8,8,5,-9,-9,-9,-9,-3,3,9,9,9,9,4,-2,-8 %N A214667 The y-coordinates of prime numbers in an Ulam spiral oriented counterclockwise with first step west. %C A214667 The eight possible orientations of the Ulam spiral can be derived from combining either A214664 or A214666 with either A214665 or A214667 as ordered pairs of coordinates. %C A214667 This spiral is rotated 180 degrees from the spiral on the March 1964 cover of Scientific American. %H A214667 William Rex Marshall, <a href="/A214667/b214667.txt">Table of n, a(n) for n = 1..10077</a> (coordinates of primes in a 325 X 325 square) %Y A214667 Cf. A000040, A063826, A214664, A214665, A214666. %K A214667 sign,easy %O A214667 1,6 %A A214667 _William Rex Marshall_, Jul 26 2012