OFFSET
0,3
MAPLE
a:= n-> add(Stirling2(n+1, q)^2*q!, q=0..n):
seq(a(n), n=0..19); # Alois P. Heinz, May 11 2020
MATHEMATICA
Table[Sum[StirlingS2[n+1, k]^2 * k!, {k, 0, n}], {n, 0, 20}] (* Vaclav Kotesovec, Jul 12 2018 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Nov 14 2005
STATUS
approved