a(n) = n^(n+1) - (n+1)^n.

Terms

a(0) =-1a(1) =-1a(2) =-1a(3) =17a(4) =399a(5) =7849a(6) =162287a(7) =3667649a(8) =91171007a(9) =2486784401a(10) =74062575399