%I #10 Mar 30 2012 16:50:47
%S 123,1123,1223,1233,11123,11223,11233,12123,12223,12233,12323,12333,
%T 111123,111223,111233,112123,112223,112233,112323,112333,121123,
%U 121223,121233,122123,122223,122233,122323,122333,123123,123223,123233,123323,123333,1111123
%N Sorted list of strings that can be obtained by starting with 123 and repeatedly doubling any substring in place.
%C The list contains A135473(n) strings of length n.
%H Alois P. Heinz, <a href="/A135475/b135475.txt">Table of n, a(n) for n = 1..10397</a> (strings with length <= 12)
%H <a href="/index/Do#repeat">Index entries for doubling substrings</a>
%Y Cf. A135473, A130838, A135479, A135017.
%K nonn,easy
%O 1,1
%A _N. J. A. Sloane_, Feb 22 2008, Mar 16 2008