E.g.f. x^3/(1-x)^2.

Terms

a(0) =0a(1) =0a(2) =0a(3) =6a(4) =48a(5) =360a(6) =2880a(7) =25200a(8) =241920a(9) =2540160a(10) =29030400a(11) =359251200a(12) =4790016000a(13) =68497228800