a(n) = 24*n^2 - 1.

Terms

a(0) =23a(1) =95a(2) =215a(3) =383a(4) =599a(5) =863a(6) =1175a(7) =1535a(8) =1943a(9) =2399a(10) =2903a(11) =3455a(12) =4055a(13) =4703a(14) =5399a(15) =6143a(16) =6935a(17) =7775a(18) =8663a(19) =9599a(20) =10583a(21) =11615a(22) =12695a(23) =13823a(24) =14999a(25) =16223a(26) =17495a(27) =18815a(28) =20183a(29) =21599