OFFSET
0,3
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..104
MATHEMATICA
f[n_, k_] := f[n, k] = f[n - 1, k] + (n - 1)f[n - 1, k - 1] + If[n == k, 1, 0]
f[_, 0] = 1;
f[0, _] = 0;
Table[Sum[f[n - k, k], {k, 0, n}], {n, 0, 100}]
PROG
(Maxima) P[0]:1$
P[n]:=(1+(n-1)*q)*P[n-1]+q^n$
makelist(sum(coeff(expand(P[n-k]), q^k), k, 0, n), n, 0, 24);
CROSSREFS
KEYWORD
nonn
AUTHOR
Emanuele Munarini, Jun 03 2011
STATUS
approved