a(n) = 400*n^2 + 2*n.

Terms

a(0) =402a(1) =1604a(2) =3606a(3) =6408a(4) =10010a(5) =14412a(6) =19614a(7) =25616a(8) =32418a(9) =40020a(10) =48422a(11) =57624a(12) =67626a(13) =78428a(14) =90030a(15) =102432a(16) =115634a(17) =129636a(18) =144438a(19) =160040a(20) =176442a(21) =193644a(22) =211646a(23) =230448a(24) =250050a(25) =270452a(26) =291654a(27) =313656a(28) =336458a(29) =360060