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Fixed point of the morphism 0 -> 01, 1 -> 1101, starting with 0.
5

%I #23 Jan 25 2018 03:02:27

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

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

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

%N Fixed point of the morphism 0 -> 01, 1 -> 1101, starting with 0.

%C The other fixed point is 1, 1, 0, 1, 1, 1, 0, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 0, 1, 1, 1, 0, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 0, 1, 1, 1, 0, 1, ... - _Michel Dekking_, Jan 22 2018

%H Clark Kimberling, <a href="/A284939/b284939.txt">Table of n, a(n) for n = 1..10000</a>

%H <a href="/index/Fi#FIXEDPOINTS">Index entries for sequences that are fixed points of mappings</a>

%e 0 -> 01-> 011101 -> 01110111011101011101 -> ...

%t s = Nest[Flatten[# /. {0 -> {0, 1}, 1 -> {1, 1, 0, 1}}] &, {0}, 6] (* A284939 *)

%t Flatten[Position[s, 0]] (* A080580 *)

%t Flatten[Position[s, 1]] (* A284941 *)

%Y Cf. A080580, A284941.

%K nonn,easy

%O 1

%A _Clark Kimberling_, Apr 18 2017

%E Name clarified by _Michel Dekking_, Jan 22 2018