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%I #18 Jul 13 2013 12:04:15
%S 2,3,5,6,8,16,17,19,34,36,39,40,42,49,69,71,74,78,80,85,132,167,175,
%T 176,180,181,225,238,261,271,320,331,338,340,341,353,365,371,507,689,
%U 690,706,721,738,746,921,932,952,990,1012,1046,1212,1351,1352,1373
%N Numbers n such that next term of Hofstadter's Q-sequence differs by 1.
%C A005185(a(n)+1) = A005185(a(n)) + 1; A081827(a(n)) = 1.
%H Reinhard Zumkeller, <a href="/A194626/b194626.txt">Table of n, a(n) for n = 1..200</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/HofstadtersQ-Sequence.html">Hofstadter's Q-Sequence</a>
%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Hofstadter_sequence">Hofstadter sequence</a>
%H <a href="/index/Ho#Hofstadter">Index entries for Hofstadter-type sequences</a>
%o (Haskell)
%o import Data.List (elemIndices)
%o a194626 n = a194626_list !! (n-1)
%o a194626_list = map (+ 1) $ elemIndices 1 a081827_list
%Y Cf. A081828, A081829, A081830.
%K nonn
%O 1,1
%A _Reinhard Zumkeller_, Sep 15 2011