a(n) = sigma(2*n^4) - sigma(n^4).

Terms

a(0) =2a(1) =32a(2) =242a(3) =512a(4) =1562a(5) =3872a(6) =5602a(7) =8192a(8) =19682a(9) =24992a(10) =32210a(11) =61952a(12) =61882a(13) =89632a(14) =189002a(15) =131072a(16) =177482a(17) =314912a(18) =275122a(19) =399872a(20) =677842a(21) =515360a(22) =585122a(23) =991232a(24) =976562a(25) =990112a(26) =1594322a(27) =1434112a(28) =1465082a(29) =3024032