%I #8 Apr 27 2017 13:01:25
%S 0,1,0,1,0,0,0,1,0,1,0,0,0,1,0,1,0,1,0,1,0,0,0,1,0,1,0,0,0,1,0,1,0,1,
%T 0,1,0,0,0,1,0,1,0,0,0,1,0,1,0,0,0,1,0,1,0,0,0,1,0,1,0,1,0,1,0,0,0,1,
%U 0,1,0,0,0,1,0,1,0,1,0,1,0,0,0,1,0,1
%N Fixed point of the morphism 0 -> 01, 1 -> 0100.
%H Clark Kimberling, <a href="/A284851/b284851.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-> 010100 -> 0101000101000101 ->
%t s = Nest[Flatten[# /. {0 -> {0, 1}, 1 -> {0, 1, 0, 0}}] &, {0}, 6] (* A284851 *)
%t Flatten[Position[s, 0]] (* A284852 *)
%t Flatten[Position[s, 1]] (* A284853 *)
%Y Cf. A284852, A284853.
%K nonn,easy
%O 1
%A _Clark Kimberling_, Apr 15 2017