Numbers whose base-3 representation has the same nonzero number of 0's and 2's.

Terms

a(0) =6a(1) =11a(2) =15a(3) =19a(4) =21a(5) =32a(6) =34a(7) =38a(8) =42a(9) =46a(10) =48a(11) =56a(12) =58a(13) =60a(14) =64a(15) =66a(16) =72a(17) =89a(18) =95a(19) =97a(20) =101a(21) =103a(22) =105a(23) =113a(24) =115a(25) =119a(26) =123a(27) =127a(28) =129a(29) =137