OFFSET
0,5
LINKS
Seiichi Manyama, Table of n, a(n) for n = 0..500
FORMULA
a(0) = 1 and a(n) = - (n-1)! * Sum_{k=1..min(3,n)} a(n-k)/(n-k)!.
D-finite with recurrence a(n) +a(n-1) +(n-1)*a(n-2) +(n-1)*(n-2)*a(n-3)=0. - R. J. Mathar, May 07 2020
MATHEMATICA
m = 25; Range[0, m]! * CoefficientList[Series[Exp[-(x + x^2/2 + x^3/3)], {x, 0, m}], x] (* Amiram Eldar, May 03 2021 *)
PROG
(PARI) N=40; x='x+O('x^N); Vec(serlaplace(exp(-x-x^2/2-x^3/3)))
CROSSREFS
KEYWORD
sign
AUTHOR
Seiichi Manyama, May 06 2020
STATUS
approved