OFFSET
0,2
FORMULA
a(n) = 1/(2*(n+1)) * Sum_{k=0..n+1} 3^k * (-1)^(n+1-k) * k^n * binomial(n+1,k).
PROG
(PARI) my(N=20, x='x+O('x^N)); Vec(serlaplace(serreverse(2*x/(3*exp(2*x)-1))/x))
(PARI) a(n) = sum(k=0, n+1, 3^k*(-1)^(n+1-k)*k^n*binomial(n+1, k))/(2*(n+1));
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Mar 08 2024
STATUS
approved