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

Terms

a(0) =256a(1) =65536a(2) =614656a(3) =2560000a(4) =7311616a(5) =16777216a(6) =33362176a(7) =59969536a(8) =100000000a(9) =157351936a(10) =236421376a(11) =342102016a(12) =479785216a(13) =655360000a(14) =875213056a(15) =1146228736a(16) =1475789056a(17) =1871773696a(18) =2342560000a(19) =2897022976a(20) =3544535296a(21) =4294967296a(22) =5158686976a(23) =6146560000a(24) =7269949696a(25) =8540717056