Numbers m such that string 9,1 occurs in the base 10 representation of m but not of m+1.

Terms

a(0) =91a(1) =191a(2) =291a(3) =391a(4) =491a(5) =591a(6) =691a(7) =791a(8) =891a(9) =919a(10) =991a(11) =1091a(12) =1191a(13) =1291a(14) =1391a(15) =1491a(16) =1591a(17) =1691a(18) =1791a(19) =1891a(20) =1919a(21) =1991a(22) =2091a(23) =2191a(24) =2291a(25) =2391a(26) =2491a(27) =2591a(28) =2691a(29) =2791