A303566 a(n) = [x^n] (Sum_{k=0..n} (k+1)!*x^k)/(Sum_{k=0..n} (k+1)!*(-x)^k).

1, 4, 8, 40, 128, 1168, 4448, 66400, 268544, 6124480, 25118336, 827294848, 3386501120, 153439657216, 624706655744, 37378784384512, 151446759993344, 11573673369828352, 46729404312578048, 4439994292732364800, 17884613664930529280, 2067374053521268559872

Offset: 0

Author

Seiichi Manyama, Apr 26 2018

Keywords

• nonn

Links

• Seiichi Manyama, Table of n, a(n) for n = 0..448

Crossrefs

Cf. A303565, A303567.

Programs

PARI

N=66; x='x+O('x^N); Vec(sum(k=0, N, (k+1)!*x^k)/sum(k=0, N, (k+1)!*(-x)^k))