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A055415
Number of points in Z^9 of norm <= n.
6
1, 19, 2869, 84663, 995241, 7129227, 35372141, 140246303, 458690081, 1318315075, 3375505573, 7945596055, 17282877369, 35516896155, 68960061837, 128236319951, 228701936081, 394678200083, 658850300869, 1072056316615
OFFSET
0,2
LINKS
FORMULA
a(n) = [x^(n^2)] theta_3(x)^9/(1 - x), where theta_3() is the Jacobi theta function. - Ilya Gutkovskiy, Apr 14 2018
CROSSREFS
Column k=9 of A302997.
Sequence in context: A172651 A183739 A277000 * A196541 A221296 A287938
KEYWORD
nonn
STATUS
approved