a(n) = (9*n + 8)^6.

Terms

a(0) =262144a(1) =24137569a(2) =308915776a(3) =1838265625a(4) =7256313856a(5) =22164361129a(6) =56800235584a(7) =128100283921a(8) =262144000000a(9) =496981290961a(10) =885842380864