a(n) = 12*n^2.

Terms

a(0) =0a(1) =12a(2) =48a(3) =108a(4) =192a(5) =300a(6) =432a(7) =588a(8) =768a(9) =972a(10) =1200a(11) =1452a(12) =1728a(13) =2028a(14) =2352a(15) =2700a(16) =3072a(17) =3468a(18) =3888a(19) =4332a(20) =4800a(21) =5292a(22) =5808a(23) =6348a(24) =6912a(25) =7500a(26) =8112a(27) =8748a(28) =9408a(29) =10092