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A349861
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Expansion of Sum_{k>=0} k * x^k/(1 + k^4 * x).
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3
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0, 1, 1, -28, 272, 10473, -1204227, 61879504, 5542428184, -2801375692615, 597270865802225, -6353098642040604, -85053828910331125224, 62048537484671306803057, -23357096658814809538526243, -10072546328972154349642665952
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OFFSET
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0,4
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LINKS
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FORMULA
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a(n) = Sum_{k=0..n} (-k^4)^(n-k) * k.
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MATHEMATICA
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a[n_] := Sum[If[k == n - k == 0, 1, (-k^4)^(n-k)] * k, {k, 0, n}]; Array[a, 16, 0] (* Amiram Eldar, Dec 03 2021 *)
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PROG
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(PARI) a(n, s=1, t=4) = sum(k=0, n, (-k^t)^(n-k)*k^s);
(PARI) my(N=20, x='x+O('x^N)); concat(0, Vec(sum(k=0, N, k*x^k/(1+k^4*x))))
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CROSSREFS
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KEYWORD
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sign
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AUTHOR
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STATUS
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approved
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