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 A287109 #10 May 22 2017 07:40:48
%S A287109 2,3,6,12,13,19,23,25,26,29,35,39,41,42,48,50,51,55,56,59,65,66,72,76,
%T A287109 78,79,85,87,88,92,93,96,102,106,108,109,113,114,117,123,125,126,129,
%U A287109 135,136,142,146,148,149,152,158,162,164,165,171,173,174,178,179
%N A287109 Positions of 0 in A287108.
%H A287109 Clark Kimberling, <a href="/A287109/b287109.txt">Table of n, a(n) for n = 1..10000</a>
%t A287109 s = Nest[Flatten[# /. {0 -> {1, 0}, 1 -> {2, 1}, 2 -> 0}] &, {0}, 10] (* A287108 *)
%t A287109 Flatten[Position[s, 0]] (* A287109 *)
%t A287109 Flatten[Position[s, 1]] (* A287110 *)
%t A287109 Flatten[Position[s, 2]] (* A287111 *)
%Y A287109 Cf. A287108, A287110, A287111.
%K A287109 nonn,easy
%O A287109 1,1
%A A287109 _Clark Kimberling_, May 21 2017