A320215 Number of multisets of nonempty words with a total of n letters over quinary alphabet such that all letters occur at least once in the multiset.

501, 10310, 129485, 1285815, 11117600, 87804401, 651039050, 4610303390, 31536998095, 210038354645, 1369653353001, 8781196628665, 55523386000940, 347061871472795, 2148545319437735, 13192142317933416, 80429793804860995, 487358723056001905, 2937204731254087895

Offset: 5

Author

Alois P. Heinz, Oct 07 2018

Keywords

• nonn

Links

• Alois P. Heinz, Table of n, a(n) for n = 5..1000

Crossrefs

Column k=5 of A257740.

Cf. A320206.

Programs

Maple

b:= proc(n, k) option remember; `if`(n=0, 1, add(add(
      d*k^d, d=numtheory[divisors](j))*b(n-j, k), j=1..n)/n)
    end:
a:= n-> (k-> add(b(n, k-i)*(-1)^i*binomial(k, i), i=0..k))(5):
seq(a(n), n=5..25);