a(n) = a(n-1) + 8*n + 4, n > 2.

Terms

a(0) =0a(1) =1a(2) =3a(3) =31a(4) =67a(5) =111a(6) =163a(7) =223a(8) =291a(9) =367a(10) =451a(11) =543a(12) =643a(13) =751a(14) =867a(15) =991a(16) =1123a(17) =1263a(18) =1411a(19) =1567a(20) =1731a(21) =1903a(22) =2083a(23) =2271a(24) =2467a(25) =2671a(26) =2883a(27) =3103a(28) =3331a(29) =3567