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 A191263 #8 Apr 14 2017 03:55:36
%S A191263 2,7,9,11,13,18,23,28,33,35,37,39,44,46,48,50,55,57,59,61,66,68,70,72,
%T A191263 77,82,87,92,94,96,98,103,108,113,118,120,122,124,129,134,139,144,146,
%U A191263 148,150,155,160,165,170,172,174,176,181,183,185,187,192,194,196,198,203,205,207,209,214,219,224,229,231,233,235,240,242,244
%N A191263 Positions of 1 in A191261.
%C A191263 Also, positions of 1 in the fixed point of the morphism 0->01, 1>000; see A284745. - _Clark Kimberling_, Apr 13 2017
%H A191263 Clark Kimberling, <a href="/A191263/b191263.txt">Table of n, a(n) for n = 1..10000</a>
%t A191263 s = Nest[Flatten[# /. {0 -> {0, 1}, 1 -> {0, 0, 0}}] &, {0}, 13]; (* A284745 *)
%t A191263 Flatten[Position[s, 0]]; (* A284746 *)
%t A191263 Flatten[Position[s, 1]]; (* A191263 *)
%Y A191263 Cf. A191261, A191250, A284745, A284746.
%K A191263 nonn,easy
%O A191263 1,1
%A A191263 _Clark Kimberling_, May 28 2011