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%I #7 Jul 26 2012 12:04:20
%S 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 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 -8,-2,4,6,8,8,8,5,-9,-9,-9,-9,-3,3,9,9,9,9,4,-2,-8
%N The y-coordinates of prime numbers in an Ulam spiral oriented counterclockwise with first step west.
%C 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 This spiral is rotated 180 degrees from the spiral on the March 1964 cover of Scientific American.
%H 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 Cf. A000040, A063826, A214664, A214665, A214666.
%K sign,easy
%O 1,6
%A _William Rex Marshall_, Jul 26 2012
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