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A349857
Expansion of Sum_{k>=0} x^k/(1 + k^3 * x).
5
1, 1, 0, -6, 37, 155, -11616, 251940, 783641, -454238419, 29895012768, -757531311386, -106105977022243, 21452688824818775, -2105573104903303616, 16702280440994303008, 48278492787774402969521, -13301912828187822051695559, 1964564462643243537548661568
OFFSET
0,4
LINKS
FORMULA
a(n) = Sum_{k=0..n} (-k^3)^(n-k).
MATHEMATICA
a[n_] := Sum[If[k == n - k == 0, 1, (-k^3)^(n-k)], {k, 0, n}]; Array[a, 19, 0] (* Amiram Eldar, Dec 03 2021 *)
PROG
(PARI) a(n, s=0, t=3) = sum(k=0, n, (-k^t)^(n-k)*k^s);
(PARI) my(N=20, x='x+O('x^N)); Vec(sum(k=0, N, x^k/(1+k^3*x)))
CROSSREFS
KEYWORD
sign
AUTHOR
Seiichi Manyama, Dec 02 2021
STATUS
approved