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Successive record-setters (maxima) in Hofstadter's Q-sequence (A005185).
3

%I #11 Jun 02 2013 20:44:57

%S 1,2,3,4,5,6,8,10,11,12,16,20,21,22,23,24,32,40,42,43,44,46,47,48,64,

%T 66,68,72,78,80,82,83,85,88,90,92,94,96,128,130,138,149,151,152,159,

%U 162,165,168,169,170

%N Successive record-setters (maxima) in Hofstadter's Q-sequence (A005185).

%C a(n) = A005185(A226245(n)).

%H Reinhard Zumkeller, <a href="/A226244/b226244.txt">Table of n, a(n) for n = 1..1000</a>

%e a(8) = 10 because the first few terms of Hofstadter's Q-sequence are 1,1,2,3,3,4,5,5,6,6,6,8,8,8,10,9 and 10 is the 8th record value.

%o (Haskell)

%o a226244 n = a226244_list !! (n-1)

%o (a226244_list, a226245_list) = unzip $ (1,1) : f 1 1 a005185_list where

%o f i v (q:qs) | q > v = (q,i) : f (i + 1) q qs

%o | otherwise = f (i + 1) v qs

%o -- _Reinhard Zumkeller_, Jun 02 2013

%Y Cf. A005185

%K nonn

%O 1,2

%A _Jeffrey Shallit_, Jun 01 2013