Numbers k such that 7 and 8 occur juxtaposed in the base-9 representation of k but not of k-1.

Terms

a(0) =71a(1) =79a(2) =152a(3) =160a(4) =233a(5) =241a(6) =314a(7) =322a(8) =395a(9) =403a(10) =476a(11) =484a(12) =557a(13) =565a(14) =638a(15) =711a(16) =727a(17) =800a(18) =808a(19) =881a(20) =889a(21) =962a(22) =970a(23) =1043a(24) =1051a(25) =1124a(26) =1132a(27) =1205a(28) =1213a(29) =1286