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%I #4 May 02 2017 10:51:17
%S 1,4,5,6,7,8,9,12,13,16,17,20,21,24,25,28,29,32,33,34,35,36,37,40,41,
%T 44,45,46,47,48,49,52,53,56,57,58,59,60,61,64,65,68,69,70,71,72,73,76,
%U 77,80,81,82,83,84,85,88,89,92,93,94,95,96,97,100,101,104
%N Positions of 1 in A285621; complement of A285622.
%C Conjecture: a(n)/n -> (1 + sqrt(5))/2 = golden ratio (A001622).
%e As a word, A285621 = 10011111100110..., in which 1 is in positions 1,4,5,6,7,...
%t s = Nest[Flatten[# /. {0 -> {1, 1}, 1 -> {1, 0, 0, 1}}] &, {0}, 10] (* A285621 *)
%t Flatten[Position[s, 0]] (* A285622 *)
%t Flatten[Position[s, 1]] (* A285623 *)
%Y Cf. A001622, A285621, A285622.
%K nonn,easy
%O 1,2
%A _Clark Kimberling_, May 01 2017