OFFSET
0,3
FORMULA
a(0) = 1; a(n) = n*a(n-1) + (-1)^n * n.
a(n) = n! - A000240(n).
E.g.f.: (1 - x * exp(-x)) / (1-x).
a(n) ~ (1 - exp(-1)) * n!. - Vaclav Kotesovec, Jan 13 2024
PROG
(PARI) my(N=30, x='x+O('x^N)); Vec(serlaplace((1-x*exp(-x))/(1-x)))
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Jan 04 2024
STATUS
approved