OFFSET
0,2
FORMULA
a(n) = [x^n] 1/((1-(n+1)*x) * (1-x)^n).
a(n) ~ exp(2) * n^n. - Vaclav Kotesovec, Apr 07 2024
PROG
(PARI) a(n) = sum(k=0, n, n^k*binomial(2*n, n-k));
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Apr 07 2024
STATUS
approved