Numbers with exactly two distinct base-3 digits.

Terms

a(0) =3a(1) =5a(2) =6a(3) =7a(4) =9a(5) =10a(6) =12a(7) =14a(8) =16a(9) =17a(10) =18a(11) =20a(12) =22a(13) =23a(14) =24a(15) =25a(16) =27a(17) =28a(18) =30a(19) =31a(20) =36a(21) =37a(22) =39a(23) =41a(24) =43a(25) =44a(26) =49a(27) =50a(28) =52a(29) =53