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A286992
Positions of 1 in A286990; complement of A286991.
4
1, 3, 4, 6, 8, 10, 12, 13, 15, 17, 19, 21, 22, 24, 25, 27, 29, 31, 33, 34, 36, 38, 40, 42, 43, 45, 46, 48, 50, 52, 54, 55, 57, 59, 61, 63, 64, 66, 68, 70, 72, 73, 75, 76, 78, 80, 82, 84, 85, 87, 89, 91, 93, 94, 96, 97, 99, 101, 103, 105, 106, 108, 110, 112
OFFSET
1,2
COMMENTS
a(n) - a(n-1) is in {1,2} for n>=2, and a(n)/n -> 6- 3*sqrt(2).
As a word, A286990 = 1011010101011010101011..., in which 1 is in positions 1,3,4,6,8,....
LINKS
MATHEMATICA
s = Nest[Flatten[# /. {0 -> 1, 1 -> {1, 1, 0}}] &, {1}, 11]; (* Sturmian word A080764 *)
w = StringJoin[Map[ToString, s]];
w1 = StringReplace[w, {"0" -> "010", "1"->"101"}]
st = ToCharacterCode[w1] - 48 ; (* A286990 *)
Flatten[Position[st, 0]]; (* A286991 *)
Flatten[Position[st, 1]]; (* A286992 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, May 19 2017
STATUS
approved