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%I #6 Sep 14 2018 14:28:42
%S 1,2,4,32,24,14112,674368,39801344,2454266992,166591027058,
%T 12820702401872,1156778646258336,119773060481140800,
%U 14004241350957965408,1791476464655904407168,247572699435320047056384,36696694077934168215974368,5825316759916541565549586176,989291135292653632945527984868
%N Number of ordered ways of writing n^3 as a sum of n squares.
%H <a href="/index/Su#ssq">Index entries for sequences related to sums of squares</a>
%F a(n) = [x^(n^3)] theta_3(x)^n, where theta_3() is the Jacobi theta function.
%F a(n) = [x^(n^3)] (Sum_{k=-infinity..infinity} x^(k^2))^n.
%t Table[SeriesCoefficient[EllipticTheta[3, 0, x]^n, {x, 0, n^3}], {n, 0, 18}]
%t Join[{1}, Table[SquaresR[n, n^3], {n, 18}]]
%Y Cf. A000290, A000578, A066535, A218494, A232173, A298671, A298938, A298939.
%K nonn
%O 0,2
%A _Ilya Gutkovskiy_, Sep 13 2018
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