a(n) = n^2 + n + 9.

Terms

a(0) =9a(1) =11a(2) =15a(3) =21a(4) =29a(5) =39a(6) =51a(7) =65a(8) =81a(9) =99a(10) =119a(11) =141a(12) =165a(13) =191a(14) =219a(15) =249a(16) =281a(17) =315a(18) =351a(19) =389a(20) =429a(21) =471a(22) =515a(23) =561a(24) =609a(25) =659a(26) =711a(27) =765a(28) =821a(29) =879