a(n) = 648*n^2 + 72*n + 1.

Terms

a(0) =721a(1) =2737a(2) =6049a(3) =10657a(4) =16561a(5) =23761a(6) =32257a(7) =42049a(8) =53137a(9) =65521a(10) =79201a(11) =94177a(12) =110449a(13) =128017a(14) =146881a(15) =167041a(16) =188497a(17) =211249a(18) =235297a(19) =260641a(20) =287281a(21) =315217a(22) =344449a(23) =374977a(24) =406801a(25) =439921a(26) =474337a(27) =510049a(28) =547057a(29) =585361