a(n) = (7*n + 6)^6.

Terms

a(0) =46656a(1) =4826809a(2) =64000000a(3) =387420489a(4) =1544804416a(5) =4750104241a(6) =12230590464a(7) =27680640625a(8) =56800235584a(9) =107918163081a(10) =192699928576a(11) =326940373369a(12) =531441000000a(13) =832972004929