a(n) = Sum_{k=0..n} abs(stirling1(n,k))*stirling2(n+1,k+1)*k!^2.

A192566

a(n) = Sum_{k=0..n} abs(stirling1(n,k))*stirling2(n+1,k+1)*k!^2.

Terms

    a(0) =1a(1) =1a(2) =7a(3) =122a(4) =3926a(5) =201444a(6) =15081256a(7) =1551423600a(8) =209964727584

External references