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A360032
Expansion of Sum_{k>=0} (k * x * (1 + (k * x)^3))^k.
2
1, 1, 4, 27, 257, 3189, 48843, 889079, 18730597, 447945714, 11983618199, 354519428597, 11490618543066, 404910044246256, 15412461332440829, 630199633730994675, 27548323149955792880, 1282044807268698303751, 63284535745130267484867
OFFSET
0,3
FORMULA
a(n) = Sum_{k=0..floor(n/4)} (n-3*k)^n * binomial(n-3*k,k).
PROG
(PARI) my(N=20, x='x+O('x^N)); Vec(sum(k=0, N, (k*x*(1+(k*x)^3))^k))
(PARI) a(n) = sum(k=0, n\4, (n-3*k)^n*binomial(n-3*k, k));
CROSSREFS
Cf. A360731.
Sequence in context: A360731 A328694 A353015 * A360833 A360835 A374812
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Feb 19 2023
STATUS
approved