|
%I #4 May 31 2017 16:14:45
%S 3,6,12,13,18,24,25,31,33,39,42,48,52,53,59,62,66,72,73,79,81,87,90,
%T 96,100,101,107,110,115,118,124,125,132,133,139,142,147,150,156,157,
%U 162,168,169,175,177,183,186,192,193,199,202,208,212,213,219,222,227
%N Positions of 3 in A287556.
%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, 2, 0, 3, 2, 0, 3, 1, 3, 1, 2, 0, 0, 3, 1, 2, 2, 0, 3, 1, with
%C 0 in positions given by A287560,
%C 1 in positions given by A287557,
%C 2 in positions given by A287558,
%C 3 in positions given by A287559.
%H Clark Kimberling, <a href="/A287560/b287560.txt">Table of n, a(n) for n = 1..10000</a>
%t s = Nest[Flatten[# /. {0 -> {0, 1, 3, 2}, 1 -> {1, 3, 2, 0}, 2 -> {3, 2, 0, 1}, 3 -> {2, 0, 1, 3}}] &, {0}, 9]; (* A287556 *)
%t Flatten[Position[s, 0]]; (* A287557 *)
%t Flatten[Position[s, 1]]; (* A287558 *)
%t Flatten[Position[s, 2]]; (* A287559 *)
%t Flatten[Position[s, 3]]; (* A287560 *)
%Y Cf. A287556, A287557, A287558, A287559 .
%K nonn,easy
%O 1,1
%A _Clark Kimberling_, May 31 2017
|
