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%I #17 Oct 21 2023 06:34:29
%S 1,0,0,0,1,1,1,1,0,0,0,1,0,0,0,1,0,0,0,1,0,0,0,1,1,1,1,0,0,0,1,1,1,1,
%T 0,0,0,1,1,1,1,0,0,0,1,1,1,1,0,0,0,1,0,0,0,1,0,0,0,1,0,0,0,1,1,1,1,0,
%U 0,0,1,0,0,0,1,0,0,0,1,0,0,0,1,1,1,1
%N Fixed point of the morphism 0->1, 1->1000.
%H Clark Kimberling, <a href="/A284680/b284680.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 1->1000->1000111-> 1000111100010001000 ->
%t s = Nest[Flatten[# /. {0 -> {1}, 1 -> {1, 0, 0, 0}}] &, {0}, 8] (* A284680 *)
%t Flatten[Position[s, 0]] (* A284681 *)
%t Flatten[Position[s, 1]] (* A284682 *)
%Y Cf. A284681, A284682.
%K nonn,easy
%O 1
%A _Clark Kimberling_, Apr 11 2017