A287458 Positions of 2 in A287455.

3, 4, 7, 10, 15, 16, 19, 22, 27, 28, 31, 36, 39, 40, 43, 46, 51, 52, 55, 58, 63, 64, 69, 70, 75, 76, 79, 82, 85, 90, 91, 96, 97, 102, 103, 106, 111, 112, 115, 118, 123, 124, 127, 130, 135, 136, 139, 144, 147, 148, 151, 154, 159, 160, 163, 166, 171, 172, 177

Offset: 1

Author

Clark Kimberling, May 30 2017

Keywords

• nonn
• easy

Comments

a(n) - a(n-1) is in {1, 3, 5} for n >= 1; also, 3n - a(n) is in {0, 1} for n >= 1. The first 20 numbers 3n - a(n) are 0, 2, 2, 2, 0, 2, 2, 2, 0, 2, 2, 0, 0, 2, 2, 2, 0, 2, 2, 2, with 0 in positions given by A287456.

Links

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

Crossrefs

Cf. A287455, A287456, A287458.

Programs

Mathematica

s = Nest[Flatten[# /. {0->{0, 1, 2}, 1->{2, 0, 1}, 2->{2, 1, 0}}] &, {0}, 9]; (*A287455*)
Flatten[Position[s, 0]]; (*A287456*)
Flatten[Position[s, 1]]; (*A189666*)
Flatten[Position[s, 2]]; (*A287458*)