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 A287410 #4 May 26 2017 16:42:54
%S A287410 3,4,7,10,13,18,19,24,25,28,33,34,37,40,45,48,49,52,55,60,61,66,67,70,
%T A287410 73,76,81,82,87,88,93,94,97,100,103,108,109,114,115,118,121,126,129,
%U A287410 130,133,138,139,142,145,148,153,154,159,160,163,168,169,174,175
%N A287410 Positions of 2 in A287407.
%C A287410 a(n) - a(n-1) is in {1,3,5} for n >= 1; also, 3n - a(n) is in {0, 2} for n >= 1. The first 20 numbers 3n - a(n) are 0, 2, 2, 2, 2, 0, 2, 0, 2, 2, 0, 2, 2, 2, 0, 0, 2, 2, 2, 0, with 0 in positions given by A287408.
%H A287410 Clark Kimberling, <a href="/A287410/b287410.txt">Table of n, a(n) for n = 1..10000</a>
%t A287410 s = Nest[Flatten[# /. {0->{0, 1, 2}, 1->{2, 1, 0}, 2->{2, 0, 1}}] &, {0}, 9]; (*A287407*)
%t A287410 Flatten[Position[s, 0]]; (*A287408*)
%t A287410 Flatten[Position[s, 1]]; (*A287409*)
%t A287410 Flatten[Position[s, 2]]; (*A287410*)
%Y A287410 Cf. A287407, A287408, A287409.
%K A287410 nonn,easy
%O A287410 1,1
%A A287410 _Clark Kimberling_, May 25 2017