a(n) = n^6*(n^4 + 1)/2.

Terms

a(0) =0a(1) =1a(2) =544a(3) =29889a(4) =526336a(5) =4890625a(6) =30256416a(7) =141296449a(8) =537001984a(9) =1743657921a(10) =5000500000a(11) =12969598081a(12) =30960175104a(13) =68931659329a(14) =144631092256a(15) =288330890625a(16) =549764202496