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A287569
Positions of 2 in A287566.
5
2, 8, 11, 13, 19, 21, 26, 32, 33, 38, 44, 47, 52, 55, 57, 62, 65, 70, 76, 79, 84, 87, 89, 94, 98, 104, 107, 109, 115, 117, 122, 128, 132, 135, 137, 142, 146, 152, 155, 157, 163, 165, 170, 176, 177, 182, 188, 191, 195, 197, 202, 208, 209, 214, 220, 223, 228
OFFSET
1,1
COMMENTS
a(n) - a(n-1) is in {1,2,3,4,5,6,7} for n >= 1; also, 4n - a(n) is in {0,1,2,3} for n >= 1. The first 20 numbers 4n - a(n) are 2, 0, 1, 3, 1, 3, 2, 0, 3, 2, 0, 1, 0, 1, 3, 2, 3, 2, 0, 1, with
0 in positions given by A287569,
1 in positions given by A287570,
2 in positions given by A287567,
3 in positions given by A287568.
LINKS
MATHEMATICA
s = Nest[Flatten[# /. {0 -> {0, 2, 3, 1}, 1 -> {2, 3, 2, 0}, 2 -> {3, 1, 0, 2}, 3 -> {1, 0, 2, 3}}] &, {0}, 9]; (* A287566 *)
Flatten[Position[s, 0]]; (* A287567 *)
Flatten[Position[s, 1]]; (* A287568 *)
Flatten[Position[s, 2]]; (* A287569 *)
Flatten[Position[s, 3]]; (* A287570 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, May 31 2017
STATUS
approved