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A287575 Positions of 3 in A287571.

%I A287575 #4 Jun 01 2017 21:09:03
%S A287575 2,7,9,16,20,22,27,29,35,37,44,46,49,56,58,63,65,72,74,79,82,87,89,96,
%T A287575 100,102,107,109,115,117,124,126,132,134,139,141,147,149,156,158,161,
%U A287575 168,170,175,178,183,185,192,195,197,204,206,209,216,218,223,226
%N A287575 Positions of 3 in A287571.
%C A287575 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 2, 1, 3, 0, 0, 2, 1, 3, 1, 3, 0, 2, 3, 0, 2, 1, 3, 0, 2, 1, with
%C A287575 0 in positions given by A287574,
%C A287575 1 in positions given by A287575,
%C A287575 2 in positions given by A287572,
%C A287575 3 in positions given by A287573.
%H A287575 Clark Kimberling, <a href="/A287575/b287575.txt">Table of n, a(n) for n = 1..10000</a>
%t A287575 s = Nest[Flatten[# /. {0 -> {0,3,1,2}, 1 -> {3,1,2,0}, 2 -> {1,2,0,3}, 3 -> {2,0,3,1}}] &, {0}, 9];   (* A287571 *)
%t A287575 Flatten[Position[s, 0]]; (* A287572 *)
%t A287575 Flatten[Position[s, 1]]; (* A287573 *)
%t A287575 Flatten[Position[s, 2]]; (* A287574 *)
%t A287575 Flatten[Position[s, 3]]; (* A287575 *)
%Y A287575 Cf. A287571, A287572, A287573, A287574.
%K A287575 nonn,easy
%O A287575 1,1
%A A287575 _Clark Kimberling_, Jun 01 2017