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 A287555 #4 May 31 2017 15:47:03
%S A287555 4,7,10,13,19,22,25,32,34,37,44,47,49,56,59,62,67,70,73,80,82,85,92,
%T A287555 95,97,104,107,110,116,119,122,125,130,133,140,143,145,152,155,158,
%U A287555 164,167,170,173,179,182,185,192,193,200,203,206,212,215,218,221,227
%N A287555 Positions of 3 in A053839.
%C A287555 a(n) - a(n-1) is in {1,2,3,4,5,6,7} for n >= 1; also, 4n - a(n) is in {0,1,2,3} for n >= 1. The first 20 numbers 4n - a(n) are 0, 1, 2, 3, 1, 2, 3, 0, 2, 3, 0, 1, 3, 0, 1, 2, 1, 2, 3, 0, with
%C A287555 0 in positions given by A287552,
%C A287555 1 in positions given by A287553,
%C A287555 2 in positions given by A287554,
%C A287555 3 in positions given by A287555.
%H A287555 Clark Kimberling, <a href="/A287555/b287555.txt">Table of n, a(n) for n = 1..10000</a>
%t A287555 s = Nest[Flatten[# /. {0 -> {0, 1, 2, 3}, 1 -> {1, 2, 3, 0}, 2 -> {2, 3, 0, 1}, 3 -> {3, 0, 1, 2}}] &, {0}, 9]; (* A053839 *)
%t A287555 Flatten[Position[s, 0]]; (* A287552 *)
%t A287555 Flatten[Position[s, 1]]; (* A287553 *)
%t A287555 Flatten[Position[s, 2]]; (* A287554 *)
%t A287555 Flatten[Position[s, 3]]; (* A287555 *)
%Y A287555 Cf. A053839, A287552, A287553, A287554.
%K A287555 nonn,easy
%O A287555 1,1
%A A287555 _Clark Kimberling_, May 31 2017