A287570 - OEIS

%I #4 May 31 2017 21:24:51

%S 3,5,12,14,20,22,27,29,34,39,41,48,49,56,58,63,66,71,73,80,81,88,90,

%T 95,99,101,108,110,116,118,123,125,129,136,138,143,147,149,156,158,

%U 164,166,171,173,178,183,185,192,196,198,203,205,210,215,217,224,225

%N Positions of 3 in A287566.

%C 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 1, 3, 0, 2, 0, 2, 1, 3, 2, 1, 3, 0, 3, 0, 2, 1, 2, 1, 3, 0, with

%C 0 in positions given by A287570,

%C 1 in positions given by A287567,

%C 2 in positions given by A287568,

%C 3 in positions given by A287569.

%H Clark Kimberling, <a href="/A287570/b287570.txt">Table of n, a(n) for n = 1..10000</a>

%t s = Nest[Flatten[# /. {0 -> {0, 2, 3, 1}, 1 -> {2, 3, 2, 0}, 2 -> {3, 1, 0, 2}, 3 -> {1, 0, 2, 3}}] &, {0}, 9];   (* A287566 *)

%t Flatten[Position[s, 0]]; (* A287567 *)

%t Flatten[Position[s, 1]]; (* A287568 *)

%t Flatten[Position[s, 2]]; (* A287569 *)

%t Flatten[Position[s, 3]]; (* A287570 *)

%Y Cf. A287566, A287567, A287568, A287569.

%K nonn,easy

%O 1,1

%A _Clark Kimberling_, May 31 2017