a(n) = 9*n^2 - 10*n + 3.

Terms

a(0) =3a(1) =2a(2) =19a(3) =54a(4) =107a(5) =178a(6) =267a(7) =374a(8) =499a(9) =642a(10) =803a(11) =982a(12) =1179a(13) =1394a(14) =1627a(15) =1878a(16) =2147a(17) =2434a(18) =2739a(19) =3062a(20) =3403a(21) =3762a(22) =4139a(23) =4534a(24) =4947a(25) =5378a(26) =5827a(27) =6294a(28) =6779a(29) =7282