a(n) = (n-1)! * Sum_{k=1..n} k^k/k!.

A054201

a(n) = (n-1)! * Sum_{k=1..n} k^k/k!.

Terms

    a(0) =1a(1) =3a(2) =15a(3) =109a(4) =1061a(5) =13081a(6) =196135a(7) =3470097a(8) =70807497a(9) =1637267473a(10) =42310099331

External references