a(n) = 4*n^4 + 1.

Terms

a(0) =5a(1) =65a(2) =325a(3) =1025a(4) =2501a(5) =5185a(6) =9605a(7) =16385a(8) =26245a(9) =40001a(10) =58565a(11) =82945a(12) =114245a(13) =153665a(14) =202501a(15) =262145a(16) =334085a(17) =419905a(18) =521285a(19) =640001a(20) =777925a(21) =937025a(22) =1119365a(23) =1327105a(24) =1562501a(25) =1827905a(26) =2125765a(27) =2458625a(28) =2829125a(29) =3240001