a(n) = 16*n^2 + 1.

Terms

a(0) =17a(1) =65a(2) =145a(3) =257a(4) =401a(5) =577a(6) =785a(7) =1025a(8) =1297a(9) =1601a(10) =1937a(11) =2305a(12) =2705a(13) =3137a(14) =3601a(15) =4097a(16) =4625a(17) =5185a(18) =5777a(19) =6401a(20) =7057a(21) =7745a(22) =8465a(23) =9217a(24) =10001a(25) =10817a(26) =11665a(27) =12545a(28) =13457a(29) =14401