A287577 - OEIS

%I #4 Jun 01 2017 21:09:19

%S 1,6,11,16,20,21,26,31,35,40,41,46,50,55,60,61,66,71,76,77,81,86,91,

%T 96,100,101,106,111,115,120,121,126,131,136,137,142,146,151,156,157,

%U 161,166,171,176,180,181,186,191,196,197,202,207,211,216,217,222,226

%N Positions of 0 in A287576.

%C a(n) - a(n-1) is in {1,4,5} for n >= 1; also, 4n - a(n) is in {0,1,2,3} for n >= 1.  The first 20 numbers 4n - a(n) are 3, 2, 1, 0, 0, 3, 2, 1, 1, 0, 3, 2, 2, 1, 0, 3, 2, 1, 0, 3, with

%C 0 in positions given by A287578,

%C 1 in positions given by A287579,

%C 2 in positions given by A287580,

%C 3 in positions given by A287577.

%H Clark Kimberling, <a href="/A287577/b287577.txt">Table of n, a(n) for n = 1..10000</a>

%t s = Nest[Flatten[# /. {0 -> {0,3,2,1}, 1 -> {3,2,1,0}, 2 -> {2,1,0,3}, 3 -> {1,0,3,2}}] &, {0}, 9];   (* A287576 *)

%t Flatten[Position[s, 0]]; (* A287577 *)

%t Flatten[Position[s, 1]]; (* A287578 *)

%t Flatten[Position[s, 2]]; (* A287579 *)

%t Flatten[Position[s, 3]]; (* A287580 *)

%Y Cf. A287576, A287578, A287579, A287580.

%K nonn,easy

%O 1,2

%A _Clark Kimberling_, Jun 01 2017