cp's OEIS Frontend

A320218 Number of multisets of nonempty words with a total of n letters over octonary alphabet such that all letters occur at least once in the multiset.

%I A320218 #4 Oct 07 2018 14:50:23
%S A320218 394353,18536744,498516252,10092149744,171141602198,2569517304288,
%T A320218 35303763087512,453509029790240,5527943088161719,64619198312435832,
%U A320218 730123641203028584,8021699561768649792,86097120229812852336,906057856878889742408,9376575130404097999848
%N A320218 Number of multisets of nonempty words with a total of n letters over octonary alphabet such that all letters occur at least once in the multiset.
%H A320218 Alois P. Heinz, <a href="/A320218/b320218.txt">Table of n, a(n) for n = 8..1000</a>
%p A320218 b:= proc(n, k) option remember; `if`(n=0, 1, add(add(
%p A320218       d*k^d, d=numtheory[divisors](j))*b(n-j, k), j=1..n)/n)
%p A320218     end:
%p A320218 a:= n-> (k-> add(b(n, k-i)*(-1)^i*binomial(k, i), i=0..k))(8):
%p A320218 seq(a(n), n=8..25);
%Y A320218 Column k=8 of A257740.
%Y A320218 Cf. A320209.
%K A320218 nonn
%O A320218 8,1
%A A320218 _Alois P. Heinz_, Oct 07 2018