%I #11 Sep 29 2019 13:19:56
%S 1,5,20,70,165,357,688,1154,1867,2907,4272,6070,8357,11307,14998,
%T 19470,24809,31211,38928,47816,58201,70361,83962,99648,117519,137521,
%U 160270,185528,213615,244649,279370,317006,358809,404823,454838,509486,568493
%N Number of points in N^4 of norm <= n.
%H Andrew Howroyd, <a href="/A055403/b055403.txt">Table of n, a(n) for n = 0..500</a>
%F a(n) = [x^(n^2)] (1 + theta_3(x))^4/(16*(1 - x)), where theta_3() is the Jacobi theta function. - _Ilya Gutkovskiy_, Apr 15 2018
%Y Column k=4 of A302998.
%K nonn
%O 0,2
%A _David W. Wilson_