OFFSET
0,3
COMMENTS
a(19) < 0.
LINKS
Seiichi Manyama, Table of n, a(n) for n = 0..374
FORMULA
a(n) = Sum_{k=0..n} (-1)^(n-k) * (2*n+1)^(k-1) * Stirling2(n,k).
PROG
(PARI) a(n) = sum(k=0, n, (-1)^(n-k)*(2*n+1)^(k-1)*stirling(n, k, 2));
CROSSREFS
KEYWORD
sign
AUTHOR
Seiichi Manyama, Nov 22 2021
STATUS
approved