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 A092739 #9 Aug 08 2016 10:20:59
%S A092739 2,4,5,8,9,16,17,32,33,44,64,65,90,128,129,171,256,257,512,513,702,
%T A092739 1024,1025,2048,2049,2732,4096,4097,5542,8192,8193,10923,16384,16385,
%U A092739 17515,22939,32768,32769,40050,43361,65536,65537,131072,131073,174764
%N A092739 Numbers n such that n*(n+1)/2 is the juxtaposition of two identical strings in binary representation.
%C A092739 2^n are terms for n>0 (A000079), 2^n + 1 are terms for n>1 (A000051).
%H A092739 Charles R Greathouse IV, <a href="/A092739/b092739.txt">Table of n, a(n) for n = 1..100</a>
%e A092739 17*(17+1)/2= 153 = 9*2^4 + 9 -> '10011001' -> '1001''1001', therefore 17 is a term.
%t A092739 tisbQ[n_]:=Module[{idn=IntegerDigits[(n(n+1))/2,2],len},len=Length[idn];EvenQ[ len]&&Take[idn,len/2]==Take[idn,-len/2]]; Select[Range[ 180000], tisbQ] (* _Harvey P. Dale_, Aug 08 2016 *)
%o A092739 (PARI) is(n)=my(L=#binary(n*=(n+1)/2)\2); n>>L==bitand(n,2^L-1) \\ _Charles R Greathouse IV_, Mar 29 2013
%Y A092739 Cf. A020330, A000217, A007088.
%K A092739 nonn,base
%O A092739 1,1
%A A092739 _Reinhard Zumkeller_, Apr 12 2004