A287454 Positions of 2 in A287451.

3, 4, 8, 11, 15, 16, 19, 23, 27, 28, 32, 36, 39, 40, 44, 47, 51, 52, 56, 60, 61, 64, 68, 72, 75, 76, 80, 83, 87, 88, 91, 95, 99, 102, 103, 107, 111, 112, 116, 119, 123, 124, 127, 131, 135, 136, 140, 144, 147, 148, 152, 155, 159, 160, 163, 167, 171, 174, 175

Offset: 1

Author

Clark Kimberling, May 30 2017

Keywords

• nonn
• easy

Comments

a(n) - a(n-1) is in {1, 3, 4} for n >= 1; also, 3n - a(n) is in {0, 1, 2} for n >= 1. The first 20 numbers 3n - a(n) are 0, 2, 1, 1, 0, 2, 2, 1, 0, 2, 1, 0, 0, 2, 1, 1, 0, 2, 1, 0, with 0 in positions given by A287452, 1 in positions given by A287454, and 2 in positions given by A287453.

Links

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

Crossrefs

Cf. A287451, A287452, A287453.

Programs

Mathematica

s = Nest[Flatten[# /. {0->{0, 1, 2}, 1->{2, 0, 1}, 2->{1, 2, 0}}] &, {0}, 9]; (*A287451*)
Flatten[Position[s, 0]]; (*A287452*)
Flatten[Position[s, 1]]; (*A287453*)
Flatten[Position[s, 2]]; (*A287454*)