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 A120884 (1/8)*number of lattice points with odd indices in a cubic lattice inside a sphere around the origin with radius 2*n. 0
 1, 4, 17, 35, 69, 114, 184, 272, 389, 528, 702, 901, 1166, 1442, 1791, 2157, 2584, 3058, 3596, 4194, 4878, 5590, 6388, 7232, 8219, 9228, 10339, 11512, 12776, 14138, 15600, 17172, 18865, 20621, 22493, 24420, 26559, 28768, 31109, 33512, 36117, 38781 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS lim n->infinity a(n)/n^3 = Pi/6. LINKS EXAMPLE 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. CROSSREFS Cf. A000605, A117609. Sequence in context: A063115 A009954 A031092 * A267766 A273683 A173511 Adjacent sequences:  A120881 A120882 A120883 * A120885 A120886 A120887 KEYWORD nonn AUTHOR Hugo Pfoertner, Jul 12 2006 STATUS approved

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Last modified July 17 20:45 EDT 2019. Contains 325109 sequences. (Running on oeis4.)