A287375 Positions of 2 in A101666.

4, 6, 10, 14, 18, 22, 26, 32, 34, 38, 42, 48, 50, 54, 60, 62, 66, 70, 74, 80, 82, 86, 92, 94, 98, 102, 106, 112, 116, 118, 122, 126, 130, 134, 138, 144, 146, 150, 156, 158, 162, 166, 170, 176, 180, 182, 186, 190, 194, 198, 202, 208, 210, 214, 220, 222, 228

Offset

1,1

Comments

4n - a(n) is in {0,2} for n >= 1. The first 20 numbers 4n - a(n) are 0, 2, 2, 2, 2, 2, 2, 0, 2, 2, 2, 0, 2, 2, 0, 2, 2, 2, 2, 0.

Links

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

Formula

a(n) = 2*A287374(n) for n >= 1.

Mathematica

s = Nest[Flatten[# /. {0 -> {0, 1}, 1 -> {1, 2}, 2 -> {1, 0}}] &, {0}, 12]   (* A101666 *)
Flatten[Position[s, 0]]  (* A287373 *)
Flatten[Position[s, 1]]  (* A287374 *)
Flatten[Position[s, 2]]  (* A287375 *)

Crossrefs

Cf. A287372, A287373, A287374.

Sequence in context: A058917 A310584 A165779 * A325042 A137860 A184335

Adjacent sequences: A287372 A287373 A287374 * A287376 A287377 A287378

Keyword

nonn,easy

Author

Clark Kimberling, May 25 2017

Status

approved