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 A287110 #8 May 22 2017 07:13:14
%S A287110 1,5,8,10,11,15,17,18,21,22,24,28,31,33,34,37,38,40,44,46,47,49,53,54,
%T A287110 58,61,63,64,68,70,71,74,75,77,81,83,84,86,90,91,95,98,100,101,104,
%U A287110 105,107,111,112,116,119,121,122,124,128,131,133,134,138,140,141
%N A287110 Positions of 1 in A287108.
%H A287110 Clark Kimberling, <a href="/A287110/b287110.txt">Table of n, a(n) for n = 1..10000</a>
%t A287110 s = Nest[Flatten[# /. {0 -> {1, 0}, 1 -> {2, 1}, 2 -> 0}] &, {0}, 10] (* A287108 *)
%t A287110 Flatten[Position[s, 0]] (* A287109 *)
%t A287110 Flatten[Position[s, 1]] (* A287110 *)
%t A287110 Flatten[Position[s, 2]] (* A287111 *)
%Y A287110 Cf. A287108, A287109, A287111.
%K A287110 nonn,easy
%O A287110 1,2
%A A287110 _Clark Kimberling_, May 21 2017