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%I #17 Aug 26 2019 08:04:55
%S 1,5,10,10,10,21,30,20,15,35,50,40,30,45,70,60,30,55,100,80,56,90,110,
%T 80,60,90,140,130,80,115,190,140,55,120,200,170,130,145,200,200,120,
%U 145,270,220,140,231,290,200,110
%N Number of nonnegative solutions of x1^2 + x2^2 + ... + x5^2 = n.
%H T. D. Noe, <a href="/A038671/b038671.txt">Table of n, a(n) for n = 0..10000</a>
%H <a href="/index/Su#ssq">Index entries for sequences related to sums of squares</a>
%F Coefficient of q^n in (1 + q + q^4 + q^9 + q^16 + q^25 + q^36 + q^49 + q^64 + ...)^5.
%F G.f.: (1 + theta_3(q))^5/32, where theta_3() is the Jacobi theta function. - _Ilya Gutkovskiy_, Aug 08 2018
%t (1 + EllipticTheta[3, 0, q])^5/32 + O[q]^50 // CoefficientList[#, q]& (* _Jean-François Alcover_, Aug 26 2019 *)
%o (PARI) seq(n)=Vec((sum(k=0, sqrtint(n), x^(k^2)) + O(x*x^n))^5) \\ _Andrew Howroyd_, Aug 08 2018
%K nonn
%O 0,2
%A _N. J. A. Sloane_
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