OFFSET
0,6
FORMULA
G.f.: Sum_{k>=0} x^k * Product_{j=0..k-1} (j + x^2).
PROG
(PARI) a(n) = sum(k=0, n\3, abs(stirling(n-2*k, k, 1)));
(PARI) my(N=30, x='x+O('x^N)); Vec(sum(k=0, N, x^k*prod(j=0, k-1, j+x^2)))
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Oct 19 2022
STATUS
approved