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%I #21 May 28 2018 02:54:53
%S 0,1,258,6821,72872,470319,2229624,8464487,27530298,78974938,
%T 206418978,497450302,1126668140,2410089243,4930872330,9670306930,
%U 18336637198,33650085029,60146112858,104730757818,178524931538,297898015114,488407670832,786658901771
%N Total sum of 8th powers of parts in all partitions of n.
%C The bivariate g.f. for the partition statistic "sum of 8th powers of the parts" is G(t,x) = 1/Product_{k>=1}(1 - t^{k^8}*x^k). The g.f. g at the Formula section has been obtained by evaluating dG/dt at t=1. - _Emeric Deutsch_, Dec 06 2015
%H Alois P. Heinz, <a href="/A229330/b229330.txt">Table of n, a(n) for n = 0..1000</a>
%H Guo-Niu Han, <a href="https://arxiv.org/abs/0804.1849">An explicit expansion formula for the powers of the Euler Product in terms of partition hook lengths</a>, arXiv:0804.1849 [math.CO], 2008.
%F a(n) = Sum_{k=1..n} A066633(n,k) * k^8.
%F G.f.: g(x) = (Sum_{k>=1} k^8*x^k/(1-x^k))/Product_{q>=1}(1-x^q). - _Emeric Deutsch_, Dec 06 2015
%F a(n) ~ 13063680*sqrt(2)*Zeta(9)/Pi^9 * exp(Pi*sqrt(2*n/3)) * n^(7/2). - _Vaclav Kotesovec_, May 28 2018
%p b:= proc(n, i) option remember; `if`(n=0, [1, 0],
%p `if`(i<1, [0, 0], `if`(i>n, b(n, i-1),
%p ((g, h)-> g+h+[0, h[1]*i^8])(b(n, i-1), b(n-i, i)))))
%p end:
%p a:= n-> b(n, n)[2]:
%p seq(a(n), n=0..40);
%p # second Maple program:
%p g := (sum(k^8*x^k/(1-x^k), k = 1..100))/(product(1-x^k, k = 1..100)): gser := series(g, x = 0, 45): seq(coeff(gser, x, m), m = 1 .. 40); # _Emeric Deutsch_, Dec 06 2015
%t (* T = A066633 *) T[n_, n_] = 1; T[n_, k_] /; k < n := T[n, k] = T[n - k, k] + PartitionsP[n - k]; T[_, _] = 0; a[n_] := Sum[T[n, k]*k^8, {k, 1, n}]; Array[a, 40, 0] (* _Jean-François Alcover_, Dec 15 2016 *)
%Y Column k=8 of A213191.
%K nonn
%O 0,3
%A _Alois P. Heinz_, Sep 20 2013
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