A286925 - OEIS

%I #7 May 25 2017 13:24:17

%S 0,0,0,0,0,1,0,0,0,0,0,1,0,0,0,0,0,0,0,1,0,0,0,0,0,1,0,0,0,0,0,0,0,1,

%T 0,0,0,0,0,1,0,0,0,0,0,1,0,0,0,0,0,0,0,1,0,0,0,0,0,1,0,0,0,0,0,0,0,1,

%U 0,0,0,0,0,1,0,0,0,0,0,1,0,0,0,0,0,0

%N {0->01,1->00}-transform of the Sturmian word A080764.

%C A080764 = 1101101110110111011011011101..., and replacing each 0 by 01 and each 1 by 00 gives 0000010000010000000100000100000001000001..., in which the positions of 0 are given by A286926, and of 1, by A286927.

%H Clark Kimberling, <a href="/A286925/b286925.txt">Table of n, a(n) for n = 1..10000</a>

%t s = Nest[Flatten[# /. {0 -> 1, 1 -> {1, 1, 0}}] &, {1}, 11]; (* Sturmian word A080764 *)

%t w = StringJoin[Map[ToString, s]];

%t w1 = StringReplace[w, {"0" -> "01", "1" -> "00"}]

%t st = ToCharacterCode[w1] - 48 ; (* A286925 *)

%t Flatten[Position[st, 0]];  (* A286926 *)

%t Flatten[Position[st, 1]];  (* A286927 *)

%Y Cf. A080764, A286926, A286927, A286688.

%K nonn,easy

%O 1

%A _Clark Kimberling_, May 18 2017