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A287577
Positions of 0 in A287576.
6
1, 6, 11, 16, 20, 21, 26, 31, 35, 40, 41, 46, 50, 55, 60, 61, 66, 71, 76, 77, 81, 86, 91, 96, 100, 101, 106, 111, 115, 120, 121, 126, 131, 136, 137, 142, 146, 151, 156, 157, 161, 166, 171, 176, 180, 181, 186, 191, 196, 197, 202, 207, 211, 216, 217, 222, 226
OFFSET
1,2
COMMENTS
a(n) - a(n-1) is in {1,4,5} 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, 2, 1, 0, 0, 3, 2, 1, 1, 0, 3, 2, 2, 1, 0, 3, 2, 1, 0, 3, with
0 in positions given by A287578,
1 in positions given by A287579,
2 in positions given by A287580,
3 in positions given by A287577.
LINKS
MATHEMATICA
s = Nest[Flatten[# /. {0 -> {0, 3, 2, 1}, 1 -> {3, 2, 1, 0}, 2 -> {2, 1, 0, 3}, 3 -> {1, 0, 3, 2}}] &, {0}, 9]; (* A287576 *)
Flatten[Position[s, 0]]; (* A287577 *)
Flatten[Position[s, 1]]; (* A287578 *)
Flatten[Position[s, 2]]; (* A287579 *)
Flatten[Position[s, 3]]; (* A287580 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Jun 01 2017
STATUS
approved