A320211 Number of sets of nonempty words with a total of n letters over denary alphabet such that all letters occur at least once in the set.

58941091, 4097382940, 159454061270, 4587784661870, 108909499300650, 2259736176893470, 42433681634931005, 737876928284127870, 12073172284265618005, 188049325030487680920, 2812707955072045999940, 40672129029056125818340, 571583937930987524954470

Offset: 10

Author

Alois P. Heinz, Oct 07 2018

Keywords

• nonn

Links

• Alois P. Heinz, Table of n, a(n) for n = 10..975

Crossrefs

Column k=10 of A319501.

Cf. A320220.

Programs

Maple

h:= proc(n, i, k) option remember; `if`(n=0, 1, `if`(i<1, 0,
      add(h(n-i*j, i-1, k)*binomial(k^i, j), j=0..n/i)))
    end:
a:= n-> (k-> add((-1)^i*binomial(k, i)*h(n$2, k-i), i=0..k))(10):
seq(a(n), n=10..25);