A287419 Positions of 0 in A287418.

1, 6, 8, 12, 14, 16, 21, 22, 26, 30, 32, 34, 39, 40, 44, 46, 51, 53, 57, 59, 61, 64, 69, 71, 75, 76, 80, 84, 86, 88, 93, 94, 98, 100, 105, 107, 111, 113, 115, 118, 123, 125, 129, 130, 134, 136, 141, 143, 147, 149, 151, 156, 157, 161, 165, 167, 169, 174, 175

Offset

1,2

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 2, 0, 1, 0, 1, 2, 0, 2, 1, 0, 1, 2, 0, 2, 1, 2, 0, 1, 0, 1, with 0 in positions given by A287420.

Links

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

Mathematica

s = Nest[Flatten[# /. {0->{0, 1, 2}, 1->{1, 2, 0}, 2->{1, 0, 2}}] &, {0}, 9]; (*A287418*)
Flatten[Position[s, 0]]; (*A287419*)
Flatten[Position[s, 1]]; (*A287420*)
Flatten[Position[s, 2]]; (*A287421*)
Position[SubstitutionSystem[{0->{0, 1, 2}, 1->{1, 2, 0}, 2->{1, 0, 2}}, {0}, {5}][[1]], 0]// Flatten (* Harvey P. Dale, Jun 21 2022 *)

Crossrefs

Cf. A287418, A287420, A287421.

Sequence in context: A354098 A026601 A287435 * A315857 A243937 A242058

Adjacent sequences: A287416 A287417 A287418 * A287420 A287421 A287422

Keyword

nonn,easy

Author

Clark Kimberling, May 25 2017

Status

approved