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A287557
Positions of 0 in A287556.
5
1, 8, 10, 15, 20, 22, 27, 29, 35, 37, 44, 46, 50, 55, 57, 64, 68, 70, 75, 77, 83, 85, 92, 94, 98, 103, 105, 112, 113, 120, 122, 127, 130, 135, 137, 144, 145, 152, 154, 159, 164, 166, 171, 173, 179, 181, 188, 190, 195, 197, 204, 206, 210, 215, 217, 224, 225
OFFSET
1,2
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 3, 0, 2, 1, 0, 2, 1, 3, 1, 3, 0, 2, 2, 1, 3, 0, 0, 2, 1, 3, with
0 in positions given by A287558,
1 in positions given by A287559,
2 in positions given by A287560,
3 in positions given by A287557.
LINKS
MATHEMATICA
s = Nest[Flatten[# /. {0 -> {0, 1, 3, 2}, 1 -> {1, 3, 2, 0}, 2 -> {3, 2, 0, 1}, 3 -> {2, 0, 1, 3}}] &, {0}, 9]; (* A287556 *)
Flatten[Position[s, 0]]; (* A287557 *)
Flatten[Position[s, 1]]; (* A287558 *)
Flatten[Position[s, 2]]; (* A287559 *)
Flatten[Position[s, 3]]; (* A287560 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, May 31 2017
STATUS
approved