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{000->null}-transform of the Pell word, A171588.
6

%I #4 May 17 2017 11:34:25

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

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

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

%N {000->null}-transform of the Pell word, A171588.

%C A171588 = 001001000100100010010010001001..., and deleting each occurrence of 000 gives 00100110011001001100110..., in which the positions of 0 are given by A286805, and of 1, by A286806.

%H Clark Kimberling, <a href="/A286804/b286804.txt">Table of n, a(n) for n = 1..10000</a>

%t s = Nest[Flatten[# /. {0 -> {0, 0, 1}, 1 -> {0}}] &, {0}, 16]; (* Pell word, A171588 *)

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

%t w1 = StringReplace[w, {"000" -> ""}];

%t st = ToCharacterCode[w1] - 48 ; (* A286804 *)

%t Flatten[Position[st, 0]]; (* A286805 *)

%t Flatten[Position[st, 1]]; (* A286806 *)

%Y Cf. A171588, A286805, A286806.

%K nonn,easy

%O 1

%A _Clark Kimberling_, May 16 2017