a(n) = 54*n^2 + 1.

Terms

a(0) =1a(1) =55a(2) =217a(3) =487a(4) =865a(5) =1351a(6) =1945a(7) =2647a(8) =3457a(9) =4375a(10) =5401a(11) =6535a(12) =7777a(13) =9127a(14) =10585a(15) =12151a(16) =13825a(17) =15607a(18) =17497a(19) =19495a(20) =21601a(21) =23815a(22) =26137a(23) =28567a(24) =31105a(25) =33751a(26) =36505a(27) =39367a(28) =42337a(29) =45415