%I #6 Jan 07 2020 13:28:02
%S 3,1,2,3,2,1,3,1,2,1,3,2,3,1,2,3,2,1,3,2,3,1,2,1,3,1,2,3,2,1,3,1,2,1,
%T 3,2,3,1,2,1,3,1,2,3,2,1,3,2,3,1,2,3,2,1,3,1,2,1,3,2,3,1,2,3,2,1,3,2,
%U 3,1,2,1,3,1,2,3,2,1,3,2,3,1,2,3,2,1,3,1,2,1,3,2,3,1,2,1,3,1,2
%N Ternary Thue-Morse sequence: closed under a->abc, b->ac, c->b.
%D M. Lothaire, Combinatorics on Words. Addison-Wesley, Reading, MA, 1983, p. 26.
%H Robert Israel, <a href="/A036584/b036584.txt">Table of n, a(n) for n = 0..10000</a>
%p S:= [3]:
%p Q:= {3=(3,1,2),1=(3,2),2=1}:
%p while nops(S) < 100 do S:= subs(Q,S) od:
%p S;
%K nonn
%O 0,1
%A _N. J. A. Sloane_.