a(n) = Sum_{d|n} (-1)^(d-1) * (n/d)^n * binomial(d+n/d-2, d-1).

A338689

a(n) = Sum_{d|n} (-1)^(d-1) * (n/d)^n * binomial(d+n/d-2, d-1).

Terms

    a(0) =1a(1) =3a(2) =28a(3) =223a(4) =3126a(5) =44660a(6) =823544a(7) =16514047a(8) =387538588a(9) =9951176994a(10) =285311670612

External references