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%I #10 Mar 11 2014 01:32:52
%S 1,3,10,15,54,63,170,255,660,693,990,1023,3510,4095,13932,14061,16254,
%T 16383,43690,65535,174420,174933,261630,262143,676500,710325,1014750,
%U 1048575,2704680,2706729,2839914,2841963,4057020,4059069,4192254,4194303
%N a(1)=1. For n>1, a(n) equals the smallest number > a(n-1) of the form a(k) U j U a(k) U j, where U represents concatenation (written in decimal) of the binary representation of the arguments, where 1<=k < n, and j = {0} or {1} or {}.
%C Each term of sequence A175335 exists in this sequence.
%e 10 (decimal), a term of the sequence, written in binary is 1010. Letting j={0}, we have that the decimal value of 1010 U 0 U 1010 U 0 = 1010010100, which is 660, is in the sequence.
%e Letting j = the empty string instead, and keeping a(k) = 10, we have the concatenation 1010 U 1010, which is 10101010. This is 170 in decimal, so 170 is in this sequence.
%Y Cf. A175335
%K base,nonn
%O 1,2
%A _Leroy Quet_, Apr 14 2010
%E Missing term 255 and many more terms added by _Max Alekseyev_, Jun 13 2011