a(n) = 15n^2 + 3n + 1.

Terms

a(0) =19a(1) =67a(2) =145a(3) =253a(4) =391a(5) =559a(6) =757a(7) =985a(8) =1243a(9) =1531a(10) =1849a(11) =2197a(12) =2575a(13) =2983a(14) =3421a(15) =3889a(16) =4387a(17) =4915a(18) =5473a(19) =6061a(20) =6679a(21) =7327a(22) =8005a(23) =8713a(24) =9451a(25) =10219a(26) =11017a(27) =11845a(28) =12703a(29) =13591