Numbers whose base-3 representation has the same number of 1's and 2's.

Terms

a(0) =0a(1) =5a(2) =7a(3) =11a(4) =15a(5) =19a(6) =21a(7) =29a(8) =33a(9) =44a(10) =45a(11) =50a(12) =52a(13) =55a(14) =57a(15) =63a(16) =68a(17) =70a(18) =76a(19) =83a(20) =87a(21) =98a(22) =99a(23) =104a(24) =106a(25) =116a(26) =128a(27) =132a(28) =135a(29) =140