A320206 Number of sets of nonempty words with a total of n letters over quinary alphabet such that all letters occur at least once in the set.

501, 9945, 121710, 1185360, 10096795, 78808600, 578849355, 4067705855, 27649153955, 183168119565, 1189058740200, 7593928600995, 47855567247145, 298255270385350, 1841612720379730, 11281413505991390, 68637389125392080, 415119249476398580, 2497526622600665470

Offset

5,1

Links

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

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))(5):
seq(a(n), n=5..25);

Crossrefs

Column k=5 of A319501.

Cf. A320215.

Sequence in context: A239046 A279275 A097425 * A320215 A233429 A121577

Adjacent sequences: A320203 A320204 A320205 * A320207 A320208 A320209

Keyword

nonn

Author

Alois P. Heinz, Oct 07 2018

Status

approved