Numbers k such that 1 and 8 occur juxtaposed in the base-10 representation of k but not of k-1.

Terms

a(0) =18a(1) =81a(2) =118a(3) =180a(4) =218a(5) =281a(6) =318a(7) =381a(8) =418a(9) =481a(10) =518a(11) =581a(12) =618a(13) =681a(14) =718a(15) =781a(16) =810a(17) =881a(18) =918a(19) =981a(20) =1018a(21) =1081a(22) =1118a(23) =1180a(24) =1218a(25) =1281a(26) =1318a(27) =1381a(28) =1418a(29) =1481