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 A287334 #9 May 25 2017 04:07:03
%S A287334 7,8,17,18,23,24,29,30,33,34,37,38,47,48,57,58,67,68,73,74,79,80,83,
%T A287334 84,87,88,97,98,103,104,109,110,113,114,117,118,127,128,133,134,139,
%U A287334 140,143,144,147,148,157,158,161,162,165,166,175,176,179,180,183,184
%N A287334 Positions of 2 in A287331.
%H A287334 Clark Kimberling, <a href="/A287334/b287334.txt">Table of n, a(n) for n = 1..10000</a>
%t A287334 s = Nest[Flatten[# /. {0 -> {1, 0}, 1 -> {2, 2}, 2 -> 0}] &, {0}, 10] (* A287331 *)
%t A287334 Flatten[Position[s, 0]] (* A287332 *)
%t A287334 Flatten[Position[s, 1]] (* A287333 *)
%t A287334 Flatten[Position[s, 2]] (* A287334 *)
%Y A287334 Cf. A287331, A287332, A287333.
%K A287334 nonn,easy
%O A287334 1,1
%A A287334 _Clark Kimberling_, May 23 2017