a(n) = (12*n + 5)^4.

Terms

a(0) =625a(1) =83521a(2) =707281a(3) =2825761a(4) =7890481a(5) =17850625a(6) =35153041a(7) =62742241a(8) =104060401a(9) =163047361a(10) =244140625a(11) =352275361a(12) =492884401a(13) =671898241a(14) =895745041a(15) =1171350625a(16) =1506138481a(17) =1908029761a(18) =2385443281a(19) =2947295521a(20) =3603000625a(21) =4362470401a(22) =5236114321a(23) =6234839521a(24) =7370050801a(25) =8653650625