a(n) = n^3*(n^4 + 1)/2.

Terms

a(0) =0a(1) =1a(2) =68a(3) =1107a(4) =8224a(5) =39125a(6) =140076a(7) =411943a(8) =1048832a(9) =2391849a(10) =5000500a(11) =9744251a(12) =17916768a(13) =31375357a(14) =52708124a(15) =85431375a(16) =134219776a(17) =205171793a(18) =306112932a(19) =446939299a(20) =640004000a(21) =900548901a(22) =1247184268a(23) =1702418807a(24) =2293242624a(25) =3051765625a(26) =4015913876a(27) =5230186443a(28) =6746475232