OFFSET
0,3
FORMULA
a(n) = - n! * Sum_{k=0..n} (-9)^k * binomial((n-k)/3,k)/(n-k)!.
PROG
(PARI) my(N=20, x='x+O('x^N)); Vec(serlaplace(-exp(x*(1-9*x)^(1/3))))
CROSSREFS
KEYWORD
sign,easy
AUTHOR
Seiichi Manyama, Apr 10 2023
STATUS
approved