A141006 - OEIS

%I #13 Oct 17 2017 14:35:57

%S 1,3,22,235,3139,49376,891491,18160071,411124024,10212362573,

%T 275543711899,8012352809874,249516568317597,8277748828228015,

%U 291219448755079278,10821916875914147551,423314732431005599479

%N E.g.f. exp(sum_{d|M} (exp(d*x)-1)/d), M=9.

%H Vincenzo Librandi, <a href="/A141006/b141006.txt">Table of n, a(n) for n = 0..200</a>

%t u[0, j_]: = 1; u[k_, j_]: = u[k, j] = Sum[Binomial[k-1, i-1]Plus@@(u[k-i, j]#^(i-1)&/@Divisors[j]), {i, k}]; Table[u[n, 9], {n, 0, 30}](* _Vincenzo Librandi_, Dec 12 2012 *)

%Y Column k=9 of A162663.

%K nonn

%O 0,2

%A _R. J. Mathar_, Jul 11 2008