a(n) = n*(n+8).

Terms

a(0) =0a(1) =9a(2) =20a(3) =33a(4) =48a(5) =65a(6) =84a(7) =105a(8) =128a(9) =153a(10) =180a(11) =209a(12) =240a(13) =273a(14) =308a(15) =345a(16) =384a(17) =425a(18) =468a(19) =513a(20) =560a(21) =609a(22) =660a(23) =713a(24) =768a(25) =825a(26) =884a(27) =945a(28) =1008a(29) =1073