A287560 Positions of 3 in A287556.

3, 6, 12, 13, 18, 24, 25, 31, 33, 39, 42, 48, 52, 53, 59, 62, 66, 72, 73, 79, 81, 87, 90, 96, 100, 101, 107, 110, 115, 118, 124, 125, 132, 133, 139, 142, 147, 150, 156, 157, 162, 168, 169, 175, 177, 183, 186, 192, 193, 199, 202, 208, 212, 213, 219, 222, 227

Offset: 1

Author

Clark Kimberling, May 31 2017

Keywords

• nonn
• easy

Comments

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

0 in positions given by A287560,

1 in positions given by A287557,

2 in positions given by A287558,

3 in positions given by A287559.

Links

• Clark Kimberling, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A287556, A287557, A287558, A287559 .

Programs

Mathematica

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 *)
Flatten[Position[s, 0]]; (* A287557 *)
Flatten[Position[s, 1]]; (* A287558 *)
Flatten[Position[s, 2]]; (* A287559 *)
Flatten[Position[s, 3]]; (* A287560 *)