a(n) = sigma(2*n^3) - sigma(n^3).

Terms

a(0) =2a(1) =16a(2) =80a(3) =128a(4) =312a(5) =640a(6) =800a(7) =1024a(8) =2186a(9) =2496a(10) =2928a(11) =5120a(12) =4760a(13) =6400a(14) =12480a(15) =8192a(16) =10440a(17) =17488a(18) =14480a(19) =19968a(20) =32000a(21) =23424a(22) =25440a(23) =40960a(24) =39062a(25) =38080a(26) =59048a(27) =51200a(28) =50520a(29) =99840