%I #12 Feb 17 2024 10:29:30
%S 18,29,310,411,512,613,714,815,916,1017,1118,1219,1320,1421,1522,1623,
%T 1724,1825,1926,2027,2128,2229,2330,2431,2532,2633,2734,2835,2936,
%U 3037,3138,3239,3340,3441,3542,3643,3744,3845,3946,4047,4148,4249
%N Concatenation of n and n+7.
%Y Cf. A001704, A020338.
%K nonn,base
%O 1,1
%A _Patrick De Geest_, May 15 1998