Numbers whose set of base-9 digits is {1,2}.

Terms

a(0) =1a(1) =2a(2) =10a(3) =11a(4) =19a(5) =20a(6) =91a(7) =92a(8) =100a(9) =101a(10) =172a(11) =173a(12) =181a(13) =182a(14) =820a(15) =821a(16) =829a(17) =830a(18) =901a(19) =902a(20) =910a(21) =911a(22) =1549a(23) =1550a(24) =1558a(25) =1559a(26) =1630a(27) =1631a(28) =1639a(29) =1640