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A229331
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Total sum of 9th powers of parts in all partitions of n.
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2
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0, 1, 514, 20199, 283370, 2256695, 12637956, 55247745, 202345886, 644749920, 1846772550, 4836548836, 11795957334, 27022021703, 58819382790, 122237638440, 244429962966, 471615005229, 882955864560, 1606698758560, 2853601781340, 4952029001892, 8423307325854
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OFFSET
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0,3
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COMMENTS
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The bivariate g.f. for the partition statistic "sum of 9th powers of the parts" is G(t,x) = 1/Product_{k>=1}(1 - t^{k^9}*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
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LINKS
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FORMULA
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a(n) = Sum_{k=1..n} A066633(n,k) * k^9.
G.f.: g(x) = (Sum_{k>=1} k^9*x^k/(1-x^k))/Product_{q>=1} (1-x^q). - Emeric Deutsch, Dec 06 2015
a(n) ~ 27648*sqrt(3)/11 * exp(Pi*sqrt(2*n/3)) * n^4. - Vaclav Kotesovec, May 28 2018
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MAPLE
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b:= proc(n, i) option remember; `if`(n=0, [1, 0],
`if`(i<1, [0, 0], `if`(i>n, b(n, i-1),
((g, h)-> g+h+[0, h[1]*i^9])(b(n, i-1), b(n-i, i)))))
end:
a:= n-> b(n, n)[2]:
seq(a(n), n=0..40);
# second Maple program:
g := (sum(k^9*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
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MATHEMATICA
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(* 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^9, {k, 1, n}]; Array[a, 40, 0] (* Jean-François Alcover, Dec 15 2016 *)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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