a(n) = 121*n^2 - 2*n.

Terms

a(0) =119a(1) =480a(2) =1083a(3) =1928a(4) =3015a(5) =4344a(6) =5915a(7) =7728a(8) =9783a(9) =12080a(10) =14619a(11) =17400a(12) =20423a(13) =23688a(14) =27195a(15) =30944a(16) =34935a(17) =39168a(18) =43643a(19) =48360a(20) =53319a(21) =58520a(22) =63963a(23) =69648a(24) =75575a(25) =81744a(26) =88155a(27) =94808a(28) =101703a(29) =108840