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 A287157 #4 May 22 2017 12:23:15
%S A287157 4,6,7,11,12,15,21,23,24,27,33,34,40,44,46,47,51,52,55,61,62,68,72,74,
%T A287157 75,78,84,88,90,91,97,99,100,104,105,108,114,116,117,120,126,127,133,
%U A287157 137,139,140,143,149,153,155,156,162,164,165,169,170,173,179,180
%N A287157 Positions of 0 in A287156.
%H A287157 Clark Kimberling, <a href="/A287157/b287157.txt">Table of n, a(n) for n = 1..10000</a>
%t A287157 s = Nest[Flatten[# /. {0 -> {1, 0}, 1 -> {2, 1}, 2 -> 0}] &, {0}, 11] (* A287156 *)
%t A287157 Flatten[Position[s, 0]] (* A287157 *)
%t A287157 Flatten[Position[s, 1]] (* A287158 *)
%t A287157 Flatten[Position[s, 2]] (* A287159 *)
%Y A287157 Cf. A287108, A287156, A287158, A287159.
%K A287157 nonn,easy
%O A287157 1,1
%A A287157 _Clark Kimberling_, May 22 2017