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 A287322 #4 May 23 2017 14:32:36
%S A287322 5,11,15,19,21,23,29,35,41,45,49,51,53,59,63,67,69,71,77,81,85,87,89,
%T A287322 95,97,99,105,107,109,115,121,127,131,135,137,139,145,151,157,161,165,
%U A287322 167,169,175,181,187,191,195,197,199,205,209,213,215,217,223,227
%N A287322 Positions of 1 in A287320.
%H A287322 Clark Kimberling, <a href="/A287322/b287322.txt">Table of n, a(n) for n = 1..10000</a>
%t A287322 s = Nest[Flatten[# /. {0 -> {1, 0}, 1 -> {2, 2}, 2 -> 0}] &, {0}, 9] (* A287175 *)
%t A287322 Flatten[Position[s, 0]] (* A287321 *)
%t A287322 Flatten[Position[s, 1]] (* A287322 *)
%t A287322 Flatten[Position[s, 2]] (* A287323 *)
%Y A287322 Cf. A287320, A287321, A287323.
%K A287322 nonn,easy
%O A287322 1,1
%A A287322 _Clark Kimberling_, May 23 2017