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%I #12 Feb 21 2023 18:25:33
%S 1,1,65,19812,16836458,30584805344,101712712528352,559155681922806328,
%T 4726278437746021089208,58187531579876705928027712,
%U 1000523517685151396828602120640,23235157037192774575979788565151104,709057406693306876515431403267191583808
%N Expansion of Sum_{k>=0} (k^3 * x/(1 - x))^k.
%H Winston de Greef, <a href="/A355496/b355496.txt">Table of n, a(n) for n = 0..152</a>
%F a(n) = Sum_{k=1..n} k^(3*k) * binomial(n-1,k-1) for n > 0.
%o (PARI) my(N=20, x='x+O('x^N)); Vec(sum(k=0, N, (k^3*x/(1-x))^k))
%o (PARI) a(n) = if(n==0, 1, sum(k=1, n, k^(3*k)*binomial(n-1, k-1)));
%Y Cf. A355494, A355495.
%Y Cf. A355472, A355493.
%K nonn
%O 0,3
%A _Seiichi Manyama_, Jul 04 2022