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%I #10 Apr 14 2018 13:05:49
%S 1,30,420,3640,21870,96936,331240,911040,2128260,4495430,8972712,
%T 16946280,29822520,49476840,80027280,127083328,193511790,282611280,
%U 409172940,590913960,825736296,1115671760,1509537960,2048372160,2698852520,3463029894
%N Number of ways of writing n as a sum of 15 squares.
%H Seiichi Manyama, <a href="/A276287/b276287.txt">Table of n, a(n) for n = 0..10000</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/SumofSquaresFunction.html">Sum of Squares Function</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/JacobiThetaFunctions.html">Jacobi Theta Functions</a>
%H <a href="/index/Su#ssq">Index entries for sequences related to sums of squares</a>
%F G.f.: theta_3(0,q)^15, where theta_3(x,q) is the third Jacobi theta function.
%t Table[SquaresR[15, n], {n, 0, 28}]
%Y Cf. similar sequences of number of ways of writing n as a sum of k squares listed in A276285.
%Y 15th column of A286815.
%K nonn,easy
%O 0,2
%A _Ilya Gutkovskiy_, Aug 27 2016