a(n) = (12*n + 9)^4.

Terms

a(0) =6561a(1) =194481a(2) =1185921a(3) =4100625a(4) =10556001a(5) =22667121a(6) =43046721a(7) =74805201a(8) =121550625a(9) =187388721a(10) =276922881a(11) =395254161a(12) =547981281a(13) =741200625a(14) =981506241a(15) =1275989841a(16) =1632240801a(17) =2058346161a(18) =2562890625a(19) =3154956561a(20) =3844124001a(21) =4640470641a(22) =5554571841a(23) =6597500625a(24) =7780827681a(25) =9116621361