OFFSET
0,3
FORMULA
a(n) = Sum_{k=0..n} |Stirling1(n,k)| * Stirling2(k+n,n).
PROG
(PARI) a(n) = sum(k=0, n, abs(stirling(n, k, 1))*stirling(k+n, n, 2));
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, May 14 2025
STATUS
approved
