a(n) = 64*n^2 + 16.

Terms

a(0) =80a(1) =272a(2) =592a(3) =1040a(4) =1616a(5) =2320a(6) =3152a(7) =4112a(8) =5200a(9) =6416a(10) =7760a(11) =9232a(12) =10832a(13) =12560a(14) =14416a(15) =16400a(16) =18512a(17) =20752a(18) =23120a(19) =25616a(20) =28240a(21) =30992a(22) =33872a(23) =36880a(24) =40016a(25) =43280a(26) =46672a(27) =50192a(28) =53840a(29) =57616