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A287124 revision #4

A287124

Positions of 2 in A287121.

1, 3, 7, 9, 16, 20, 22, 26, 28, 35, 45, 49, 51, 58, 62, 64, 68, 70, 77, 81, 83, 87, 89, 96, 106, 110, 112, 119, 129, 139, 143, 145, 152, 156, 158, 162, 164, 171, 181, 185, 187, 194, 198, 200, 204, 206, 213, 217, 219, 223, 225, 232, 242, 246, 248, 255, 259

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

LINKS

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

MATHEMATICA

s = Nest[Flatten[# /. {0 -> {1, 0}, 1 -> {2, 0}, 2 -> 1}] &, {0}, 12] (* A287121 *)

Flatten[Position[s, 0]] (* A287122 *)

Flatten[Position[s, 1]] (* A287123 *)

Flatten[Position[s, 2]] (* A287124 *)

CROSSREFS

Cf. A287121, A287122, A287123.