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A089029 a(n)=n if Hofstadter's Q-sequence increases A005185(n-1)->A005185(n), a(n)=1 otherwise.

%I A089029 #10 Mar 30 2012 17:38:52
%S A089029 1,3,4,1,6,7,1,9,1,1,12,1,1,15,1,17,18,1,20,1,1,1,24,1,1,27,1,1,1,31,
%T A089029 1,1,34,35,1,37,38,1,40,41,1,43,1,1,1,1,48,1,50,51,1,1,54,1,1,57,1,59,
%U A089029 1,1,1,63,1,1,66,1,1,69,70,1,72,73,1,75,1,77,1,79,80,81,1,1,84,1,86,87,1,1
%N A089029 a(n)=n if Hofstadter's Q-sequence increases A005185(n-1)->A005185(n), a(n)=1 otherwise.
%C A089029 a(n)=n if Q(n) > Q(n-1), and a(n) =1 if Q(n) <= Q(n-1).
%F A089029 a(n) = n if A081827(n-1)>0; a(n) = 1 if A081827(n-1) <=0. [_R. J. Mathar_, Dec 08 2010]
%t A089029 Hofstadter[n_Integer?Positive] := Hofstadter[n] = Hofstadter[n - Hofstadter[n-1]] + Hofstadter[n - Hofstadter[n-2]] Hofstadter[1] = Hofstadter[2] = 1 digits=200 a=Table[If[Hofstadter[n]-Hofstadter[n-1]>0, n, 1], {n, 2, digits}]
%Y A089029 Cf. A005185, A081827.
%K A089029 nonn
%O A089029 2,2
%A A089029 _Roger L. Bagula_, Nov 12 2003