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1-limiting word of the morphism 0->10, 1-> 0000.
4

%I #4 Apr 20 2017 09:24:17

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

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

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

%N 1-limiting word of the morphism 0->10, 1-> 0000.

%C The morphism 0->10, 1->0000 has two limiting words. If the number of iterations is even, the 0-word evolves from 0 -> 10 -> 000010 -> 10101010000010 -> 00001000001000001000001010101010000010; if the number of iterations is odd, the 1-word evolves from 0 -> 10 -> 000010 -> 10101010000010, as in A285128.

%H Clark Kimberling, <a href="/A285128/b285128.txt">Table of n, a(n) for n = 1..10000</a>

%t s = Nest[Flatten[# /. {0 -> {1, 0}, 1 -> {0, 0, 0, 0}}] &, {0}, 13]; (* A285128 *)

%t Flatten[Position[s, 0]]; (* A285129 *)

%t Flatten[Position[s, 1]]; (* A285130 *)

%Y Cf. A285125, A285128, A285130.

%K nonn,easy

%O 1

%A _Clark Kimberling_, Apr 19 2017