a(n) = 169*n^2 - 2*n.

Terms

a(0) =167a(1) =672a(2) =1515a(3) =2696a(4) =4215a(5) =6072a(6) =8267a(7) =10800a(8) =13671a(9) =16880a(10) =20427a(11) =24312a(12) =28535a(13) =33096a(14) =37995a(15) =43232a(16) =48807a(17) =54720a(18) =60971a(19) =67560a(20) =74487a(21) =81752a(22) =89355a(23) =97296a(24) =105575a(25) =114192a(26) =123147a(27) =132440a(28) =142071a(29) =152040