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A298937 Number of ordered ways of writing n^2 as a sum of n positive cubes. 2

%I #4 Jan 29 2018 21:12:22

%S 1,1,0,0,0,0,0,7,1,0,0,9240,34650,1716,48477,551915,6726720,89973520,

%T 102639744,1824625081,9915389400,30143458884,278196062760,

%U 1995766236541,6611689457736,64547920386450,236756174748626,2315743488707806

%N Number of ordered ways of writing n^2 as a sum of n positive cubes.

%H <a href="/index/Su#ssq">Index entries for sequences related to sums of cubes</a>

%F a(n) = [x^(n^2)] (Sum_{k>=1} x^(k^3))^n.

%e a(7) = 7 because we have [8, 8, 8, 8, 8, 8, 1], [8, 8, 8, 8, 8, 1, 8], [8, 8, 8, 8, 1, 8, 8], [8, 8, 8, 1, 8, 8, 8], [8, 8, 1, 8, 8, 8, 8], [8, 1, 8, 8, 8, 8, 8] and [1, 8, 8, 8, 8, 8, 8].

%t Join[{1}, Table[SeriesCoefficient[Sum[x^k^3, {k, 1, Floor[n^(2/3) + 1]}]^n, {x, 0, n^2}], {n, 1, 27}]]

%Y Cf. A000290, A000578, A023358, A030272, A218495, A259792, A291700, A298671, A298672, A298934, A298936.

%K nonn

%O 0,8

%A _Ilya Gutkovskiy_, Jan 29 2018

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