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A286903
{0->00}-transform of the Sturmian word A080764.
3
1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 1
OFFSET
1
COMMENTS
A080764 = 1101101110110111011011011101..., and replacing each 0 by 00 gives
1100110011100110011100110011001..., in which the positions of 0 are given by A286904, and of 1, by A286905.
LINKS
FORMULA
a(n) = floor(n*r) - floor((n+2)*r) + 1, where r = (3-sqrt(2))/7. - Ridouane Oudra, Nov 21 2024
MAPLE
r:=(3-sqrt(2))/7: seq(floor(n*r)-floor((n+2)*r)+1, n=1..100); # Ridouane Oudra, Nov 21 2024
MATHEMATICA
s = Nest[Flatten[# /. {0 -> 1, 1 -> {1, 1, 0}}] &, {1}, 7] (* A080764 *)
w = StringJoin[Map[ToString, s]]
w1 = StringReplace[w, {"0" -> "00"}]
st = ToCharacterCode[w1] - 48 ; (* A286903 *)
Flatten[Position[st, 0]]; (* A286904 *)
Flatten[Position[st, 1]]; (* A286905 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, May 17 2017
STATUS
approved