A043259 - OEIS

%I #8 Aug 24 2021 06:31:24

%S 79,97,179,197,279,297,379,397,479,497,579,597,679,697,779,790,879,

%T 897,970,997,1079,1097,1179,1197,1279,1297,1379,1397,1479,1497,1579,

%U 1597,1679,1697,1779,1790,1879,1897,1970,1997,2079

%N Numbers k such that 7 and 9 occur juxtaposed in the base-10 representation of k but not of k-1.

%K nonn,base

%O 1,1

%A _Clark Kimberling_