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A287398
Positions of 0 in A287397.
5
1, 6, 8, 11, 15, 16, 21, 22, 26, 30, 31, 35, 38, 42, 43, 46, 51, 53, 56, 60, 61, 64, 69, 71, 75, 76, 80, 83, 87, 88, 91, 96, 98, 102, 103, 107, 111, 112, 116, 119, 123, 124, 127, 132, 134, 136, 141, 143, 146, 150, 151, 156, 157, 161, 165, 166, 170, 173, 177
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, 0, 1, 1, 0, 2, 0, 2, 1, 0, 2, 1, 1, 0, 2, 2, 0, 1, 1, 0, with 0 in positions given by A287399.
LINKS
MATHEMATICA
s = Nest[Flatten[# /. {0->{0, 1, 2}, 1->{2, 1, 0}, 2->{1, 0, 2}}] &, {0}, 9]; (*A287397*)
Flatten[Position[s, 0]]; (*A287398*)
Flatten[Position[s, 1]]; (*A287399*)
Flatten[Position[s, 2]]; (*A287400*)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, May 25 2017
STATUS
approved