OFFSET
0,2
FORMULA
a(n) = Sum_{k=0..n} (Product_{j=0..k-1} (3*j-4)) * |Stirling1(n,k)|.
PROG
(PARI) a(n) = sum(k=0, n, prod(j=0, k-1, 3*j-4)*abs(stirling(n, k, 1)));
CROSSREFS
KEYWORD
sign,easy
AUTHOR
Seiichi Manyama, Sep 05 2024
STATUS
approved