a(n) = (6*n + 2)^3.

Terms

a(0) =8a(1) =512a(2) =2744a(3) =8000a(4) =17576a(5) =32768a(6) =54872a(7) =85184a(8) =125000a(9) =175616a(10) =238328a(11) =314432a(12) =405224a(13) =512000a(14) =636056a(15) =778688a(16) =941192a(17) =1124864a(18) =1331000a(19) =1560896a(20) =1815848a(21) =2097152a(22) =2406104a(23) =2744000a(24) =3112136