OFFSET
0,4
MAPLE
a := n -> add((-1)^k*pochhammer(k - n, k)*Stirling2(n - k, k), k = 0..iquo(n, 2)):
seq(a(n), n = 0..24);
PROG
CROSSREFS
KEYWORD
nonn
AUTHOR
Peter Luschny, May 04 2023
STATUS
approved