cp's OEIS Frontend

A320220 Number of multisets of nonempty words with a total of n letters over denary alphabet such that all letters occur at least once in the multiset.

%I A320220 #5 Oct 07 2018 14:55:58
%S A320220 58941091,4143348470,162731313045,4718107140980,112729591991185,
%T A320220 2351902614090062,44373396691290660,774761803780874980,
%U A320220 12721776529833584465,198768703664184994530,2981185419002290273673,43212794112241851734090,608596903477972496493095
%N A320220 Number of multisets of nonempty words with a total of n letters over denary alphabet such that all letters occur at least once in the multiset.
%H A320220 Alois P. Heinz, <a href="/A320220/b320220.txt">Table of n, a(n) for n = 10..975</a>
%p A320220 b:= proc(n, k) option remember; `if`(n=0, 1, add(add(
%p A320220       d*k^d, d=numtheory[divisors](j))*b(n-j, k), j=1..n)/n)
%p A320220     end:
%p A320220 a:= n-> (k-> add(b(n, k-i)*(-1)^i*binomial(k, i), i=0..k))(10):
%p A320220 seq(a(n), n=10..25);
%Y A320220 Column k=10 of A257740.
%Y A320220 Cf. A320211.
%K A320220 nonn
%O A320220 10,1
%A A320220 _Alois P. Heinz_, Oct 07 2018