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A287518
Positions of 1 in A287516.
4
2, 4, 9, 10, 14, 18, 20, 24, 25, 28, 32, 36, 38, 40, 45, 47, 51, 52, 56, 58, 63, 65, 69, 70, 73, 77, 81, 82, 86, 90, 92, 94, 99, 101, 105, 106, 110, 112, 117, 118, 122, 126, 128, 132, 133, 137, 139, 144, 146, 150, 151, 154, 158, 162, 164, 166, 171, 172, 176
OFFSET
1,1
COMMENTS
a(n) - a(n-1) is in {1, 2, 3, 4, 5} for n >= 1; also, 3n - a(n) is in {0, 1} for n >= 1. The first 20 numbers 3n - a(n) are 1, 2, 0, 2, 1, 0, 1, 0, 2, 2, 1, 0, 1, 2, 0, 1, 0, 2, 1, 2, with 0 in positions given by A287518.
LINKS
MATHEMATICA
s = Nest[Flatten[# /. {0->{0, 1, 2}, 1->{1, 0, 2}, 2->{0, 2, 1}}] &, {0}, 9]; (*A287516*)
Flatten[Position[s, 0]]; (*A287517*)
Flatten[Position[s, 1]]; (*A287518*)
Flatten[Position[s, 2]]; (*A189630*)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, May 30 2017
STATUS
approved