OFFSET
0,4
LINKS
Seiichi Manyama, Table of n, a(n) for n = 0..421
FORMULA
a(n) = Sum_{k=0..n} (n-k+1)^(k-1) * Stirling1(n,k).
MATHEMATICA
a[n_] := Sum[(n - k + 1)^(k - 1)*StirlingS1[n, k], {k, 0, n}]; Array[a, 22, 0] (* Amiram Eldar, Nov 23 2021 *)
PROG
(PARI) a(n) = sum(k=0, n, (n-k+1)^(k-1)*stirling(n, k, 1));
CROSSREFS
KEYWORD
sign
AUTHOR
Seiichi Manyama, Nov 22 2021
STATUS
approved
