a(n) = 441*n^2 - 2*n.

Terms

a(0) =439a(1) =1760a(2) =3963a(3) =7048a(4) =11015a(5) =15864a(6) =21595a(7) =28208a(8) =35703a(9) =44080a(10) =53339a(11) =63480a(12) =74503a(13) =86408a(14) =99195a(15) =112864a(16) =127415a(17) =142848a(18) =159163a(19) =176360a(20) =194439a(21) =213400a(22) =233243a(23) =253968a(24) =275575a(25) =298064a(26) =321435a(27) =345688a(28) =370823a(29) =396840