a(n) = (n^12 + n^6)/2.

Terms

a(0) =0a(1) =1a(2) =2080a(3) =266085a(4) =8390656a(5) =122078125a(6) =1088414496a(7) =6920702425a(8) =34359869440a(9) =141215033961a(10) =500000500000