A286688 - OEIS

%I #4 May 13 2017 17:21:34

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

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

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

%N {0->00, 1->10}-transform of the Pell word, A171588.

%H Clark Kimberling, <a href="/A286688/b286688.txt">Table of n, a(n) for n = 1..10000</a>

%e As a word, A171588 = 001001000100100010010010001001000..., and replacing each 0 by 00 and each 1 by 10 gives 00001000001000000010000010...

%t s = Nest[Flatten[# /. {0 -> {0, 0, 1}, 1 -> {0}}] &, {0}, 6] (* A171588 *)

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

%t w1 = StringReplace[w, {"0" -> "00", "1"->"10"}]

%t st = ToCharacterCode[w1] - 48 ; (* A286688 *)

%t Flatten[Position[st, 0]];  (* A286689 *)

%t Flatten[Position[st, 1]];  (* A286690 *)

%Y Cf. A171588, A286689, A286690.

%K nonn,easy

%O 1

%A _Clark Kimberling_, May 13 2017