%I #4 Apr 30 2017 11:31:04
%S 5,6,9,10,17,18,21,22,29,30,33,34,41,42,45,46,49,50,53,54,57,58,61,62,
%T 69,70,73,74,81,82,85,86,89,90,93,94,97,98,101,102,109,110,113,114,
%U 121,122,125,126,133,134,137,138,145,146,149,150,157,158,161,162
%N Positions of 0 in A285504; complement of A285506.
%C Conjecture: a(n)/n -> (3+sqrt(5))/2.
%H Clark Kimberling, <a href="/A285505/b285505.txt">Table of n, a(n) for n = 1..10000</a>
%e As a word, A285504 = 11110011001..., in which 0 is in positions 5,6,9,10,...
%t s = Nest[Flatten[# /. {0 -> {1, 1}, 1 -> {0, 0, 1, 1}}] &, {0}, 8] (* A285501 *)
%t Flatten[Position[s, 0]] (* A285502 *)
%t Flatten[Position[s, 1]] (* A285503 *)
%Y Cf. A285501, A285504, A285506.
%K nonn,easy
%O 1,1
%A _Clark Kimberling_, Apr 30 2017