OFFSET
0,2
LINKS
Seiichi Manyama, Table of n, a(n) for n = 0..450
FORMULA
a(n) ~ 4*(n-1)! if n is even and a(n) ~ 2*n! if n is odd. - Vaclav Kotesovec, May 02 2018
PROG
(PARI) N=66; x='x+O('x^N); Vec(sum(k=0, N, k!*x^k)/sum(k=0, N, k!*(-x)^k))
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Apr 26 2018
STATUS
approved