a(n) = Sum_{i=0..n} (i+1)*n^i.

Terms

a(0) =1a(1) =3a(2) =17a(3) =142a(4) =1593a(5) =22461a(6) =380713a(7) =7526268a(8) =169826513a(9) =4303999495a(10) =120987654321