This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A138168 #7 Oct 07 2015 19:20:43
%S A138168 1,2,6,7,8,9,12,20,21,22,23,26,27,29,38,44,45,46,48,49,50,51,52,53,54,
%T A138168 55,56,57,58,59,60,61,62,71,78,79,87,92,93,94,95,103,110,111,112,113,
%U A138168 114,115,116,117,118,119,120,121,122,123,124,125,126,127,128,129,130
%N A138168 Numbers containing their length in binary representation.
%H A138168 R. Zumkeller, <a href="/A138168/b138168.txt">Table of n, a(n) for n = 1..10000</a>
%e A138168 20 ->'10100', length = 5 ->'101', therefore 20 is a term;
%e A138168 200 ->'11001000', length = 8 ->'1000', therefore 200 is a term.
%t A138168 lbrQ[n_]:=Module[{idn2=IntegerDigits[n,2]},SequenceCount[idn2, IntegerDigits[ Length[ idn2],2]]>0]; Select[Range[200],lbrQ] (* The program uses the SequenceCount function from Mathematica version 10 *) (* _Harvey P. Dale_, Oct 07 2015 *)
%Y A138168 Cf. A070939, A138166, A138167.
%K A138168 nonn,base
%O A138168 1,2
%A A138168 _Reinhard Zumkeller_, Mar 03 2008