A287446 Positions of 2 in A287443.

3, 4, 8, 11, 15, 16, 21, 23, 25, 30, 32, 34, 39, 40, 44, 47, 51, 52, 57, 58, 62, 66, 68, 70, 74, 78, 79, 84, 85, 89, 93, 95, 97, 101, 105, 106, 111, 112, 116, 119, 123, 124, 129, 131, 133, 138, 140, 142, 147, 148, 152, 155, 159, 160, 165, 166, 170, 173, 177

Offset: 1

Author

Clark Kimberling, May 26 2017

Keywords

• nonn
• easy

Comments

a(n) - a(n-1) is in {1, 2, 3, 4, 5} 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, 0, 1, 2, 0, 1, 2, 0, 2, 1, 1, 0, 2, 0, 2, with 0 in positions given by A287444.

Links

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

Crossrefs

Cf. A287443, A287444, A287445.

Programs

Mathematica

s = Nest[Flatten[# /. {0->{0, 1, 2}, 1->{2, 0, 1}, 2->{0, 2, 1}}] &, {0}, 9]; (*A287443*)
Flatten[Position[s, 0]]; (*A287444*)
Flatten[Position[s, 1]]; (*A287445*)
Flatten[Position[s, 2]]; (*A287446*)