a(n) = 8*n^2 - 9*n + 3.

Terms

a(0) =3a(1) =2a(2) =17a(3) =48a(4) =95a(5) =158a(6) =237a(7) =332a(8) =443a(9) =570a(10) =713a(11) =872a(12) =1047a(13) =1238a(14) =1445a(15) =1668a(16) =1907a(17) =2162a(18) =2433a(19) =2720a(20) =3023a(21) =3342a(22) =3677a(23) =4028a(24) =4395a(25) =4778a(26) =5177a(27) =5592a(28) =6023a(29) =6470