%I #4 Apr 30 2017 11:30:59
%S 1,1,1,1,0,0,1,1,0,0,1,1,1,1,1,1,0,0,1,1,0,0,1,1,1,1,1,1,0,0,1,1,0,0,
%T 1,1,1,1,1,1,0,0,1,1,0,0,1,1,0,0,1,1,0,0,1,1,0,0,1,1,0,0,1,1,1,1,1,1,
%U 0,0,1,1,0,0,1,1,1,1,1,1,0,0,1,1,0,0
%N 1-limiting word of the morphism 0->11, 1-> 0011.
%C The morphism 0->11, 1-> 0011 has two limiting words. If the number of iterations is even, the 0-word evolves from 0 -> 11 -> 00110011 -> 111100110011111100110011 -> 0011001100110011111100110011111100110011...; if the number of iterations is odd, the 1-word evolves from 0 -> 11 -> 00110011 -> 111100110011111100110011, as in A285504.
%H Clark Kimberling, <a href="/A285504/b285504.txt">Table of n, a(n) for n = 1..10000</a>
%t s = Nest[Flatten[# /. {0 -> {1, 1}, 1 -> {0, 0, 1, 1}}] &, {0}, 9] (* A285504 *)
%t Flatten[Position[s, 0]] (* A285505 *)
%t Flatten[Position[s, 1]] (* A285506 *)
%Y Cf. A285501, A285505, A285506, A285518.
%K nonn,easy
%O 1
%A _Clark Kimberling_, Apr 30 2017