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A287456
Positions of 0 in A287455.
4
1, 5, 9, 12, 13, 17, 21, 23, 25, 30, 32, 34, 37, 41, 45, 48, 49, 53, 57, 59, 61, 66, 67, 71, 73, 77, 81, 84, 86, 88, 93, 94, 98, 100, 104, 108, 109, 113, 117, 120, 121, 125, 129, 131, 133, 138, 140, 142, 145, 149, 153, 156, 157, 161, 165, 167, 169, 174, 175
OFFSET
1,2
COMMENTS
a(n) - a(n-1) is in {1, 2, 3, 4, 5} for n >= 1; also, 3n - a(n) is in {0, 1, 2} for n >= 1. The first 20 numbers 3n - a(n) are 2, 1, 0, 0, 2, 1, 0, 1, 2, 0, 1, 2, 2, 1, 0, 0, 2, 1, 0, 1, with 0 in positions given by A287452, 1 in positions given by A287454, and 2 in positions given by A287458.
LINKS
MATHEMATICA
s = Nest[Flatten[# /. {0->{0, 1, 2}, 1->{2, 0, 1}, 2->{2, 1, 0}}] &, {0}, 9]; (*A287455*)
Flatten[Position[s, 0]]; (*A287456*)
Flatten[Position[s, 1]]; (*A189666*)
Flatten[Position[s, 2]]; (*A287458*)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, May 30 2017
STATUS
approved