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%I #4 May 30 2013 13:14:26
%S 1,4,17,35,69,114,184,272,389,528,702,901,1166,1442,1791,2157,2584,
%T 3058,3596,4194,4878,5590,6388,7232,8219,9228,10339,11512,12776,14138,
%U 15600,17172,18865,20621,22493,24420,26559,28768,31109,33512,36117,38781
%N (1/8)*number of lattice points with odd indices in a cubic lattice inside a sphere around the origin with radius 2*n.
%C lim n->infinity a(n)/n^3 = Pi/6.
%e a(2)=4 because the 4 lattice points in the first octant (x,y,z)={(1,1,1), (1,1,3), (1,3,1), (3,1,1)} all satisfy x^2+y^2+z^2 < (2*2)^2.
%Y Cf. A000605, A117609.
%K nonn
%O 1,2
%A _Hugo Pfoertner_, Jul 12 2006
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