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A319289 The x coordinates of the shell enumeration of N X N where N = {0, 1, 2, ...} (A319514).

%I A319289 #7 Sep 23 2018 05:36:54
%S A319289 0,0,1,1,2,2,2,1,0,0,1,2,3,3,3,3,4,4,4,4,4,3,2,1,0,0,1,2,3,4,5,5,5,5,
%T A319289 5,5,6,6,6,6,6,6,6,5,4,3,2,1,0,0,1,2,3,4,5,6,7,7,7,7,7,7,7,7,8,8,8,8,
%U A319289 8,8,8,8,8,7,6,5,4,3,2,1,0,0,1,2,3,4,5
%N A319289 The x coordinates of the shell enumeration of N X N where N = {0, 1, 2, ...} (A319514).
%C A319289 See A319514 for comments and references.
%H A319289 Peter Luschny, <a href="/A319289/b319289.txt">Table of n, a(n) for n = 0..10000</a>
%o A319289 (Julia)
%o A319289 function A319289(n)
%o A319289     m = x = isqrt(n)
%o A319289     y = n - x^2
%o A319289     x <= y && ((x, y) = (2x - y, x))
%o A319289     isodd(m) ? y : x
%o A319289 end
%Y A319289 Cf. A319514.
%K A319289 nonn
%O A319289 0,5
%A A319289 _Peter Luschny_, Sep 23 2018