OFFSET
0,2
FORMULA
a(n) = 3 * Sum_{k=0..n} (n+3)^(k-1) * Stirling2(n,k).
PROG
(PARI) a(n) = 3*sum(k=0, n, (n+3)^(k-1)*stirling(n, k, 2));
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Oct 15 2024
STATUS
approved