a(n) = n! - n^3.

Terms

a(0) =1a(1) =0a(2) =-6a(3) =-21a(4) =-40a(5) =-5a(6) =504a(7) =4697a(8) =39808a(9) =362151a(10) =3627800a(11) =39915469a(12) =478999872a(13) =6227018603a(14) =87178288456