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 A287159 #4 May 22 2017 12:23:35
%S A287159 1,8,13,16,18,25,28,30,35,37,41,48,53,56,58,63,65,69,76,79,81,85,92,
%T A287159 94,101,106,109,111,118,121,123,128,130,134,141,144,146,150,157,159,
%U A287159 166,171,174,176,181,183,187,194,196,203,208,211,213,217,224,229,232
%N A287159 Positions of 2 in A287156.
%H A287159 Clark Kimberling, <a href="/A287159/b287159.txt">Table of n, a(n) for n = 1..10000</a>
%t A287159 s = Nest[Flatten[# /. {0 -> {1, 0}, 1 -> {2, 1}, 2 -> 0}] &, {0}, 11] (* A287156 *)
%t A287159 Flatten[Position[s, 0]] (* A287157 *)
%t A287159 Flatten[Position[s, 1]] (* A287158 *)
%t A287159 Flatten[Position[s, 2]] (* A287159 *)
%Y A287159 Cf. A287108, A287156, A287157, A287158.
%K A287159 nonn,easy
%O A287159 1,2
%A A287159 _Clark Kimberling_, May 22 2017