Numbers n such that string 2,0 occurs in the base 9 representation of n but not of n+1.

Terms

a(0) =18a(1) =99a(2) =170a(3) =180a(4) =261a(5) =342a(6) =423a(7) =504a(8) =585a(9) =666a(10) =747a(11) =828a(12) =899a(13) =909a(14) =990a(15) =1071a(16) =1152a(17) =1233a(18) =1314a(19) =1395a(20) =1538a(21) =1557a(22) =1628a(23) =1638a(24) =1719a(25) =1800a(26) =1881a(27) =1962a(28) =2043a(29) =2124