A334564 E.g.f.: exp(-(x + x^2 + x^3 + x^4)).

1, -1, -1, -1, 1, 139, 151, -1429, -19039, -170281, 517231, 12144439, 108063649, 294730019, -12338255929, -161010756061, -834576525119, 10909293532591, 350211422028511, 3176429907556079, -8268487440910399, -816508001025525061, -14017265801126968841, -55997107943920795301

Offset: 0

Author

Seiichi Manyama, May 06 2020

Keywords

• sign

Links

• Seiichi Manyama, Table of n, a(n) for n = 0..500

Crossrefs

Column 4 of A334561.

Cf. A193930, A334570.

Programs

Mathematica

m = 25; Range[0, m]! * CoefficientList[Series[Exp[-(x + x^2 + x^3 + x^4)], {x, 0, m}], x] (* Amiram Eldar, May 03 2021 *)

PARI

N=40; x='x+O('x^N); Vec(serlaplace(exp(-x-x^2-x^3-x^4)))

Formula

a(0) = 1 and a(n) = - (n-1)! * Sum_{k=1..min(4,n)} k*a(n-k)/(n-k)!.