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%I #18 Aug 02 2018 02:37:22
%S 1,5,6,10,11,14,15,20,21,22,24,25,28,29,33,34,37,38,39,43,44,50,51,53,
%T 54,57,58,61,62,67,68,69,74,75,76,78,81,82,84,85,89,90,93,96,97,100,
%U 101,107,108,109,111,112,115,116,118,119,124,125,128,129
%N Where the odd terms appear in A064413.
%C Complement of A064953; A195376(a(n)) = 1. [_Reinhard Zumkeller_, Sep 17 2001]
%H Reinhard Zumkeller, <a href="/A064957/b064957.txt">Table of n, a(n) for n = 1..10000</a>
%H J. C. Lagarias, E. M. Rains and N. J. A. Sloane, <a href="https://arxiv.org/abs/math/0204011">The EKG sequence</a>, arXiv:math/0204011 [math.NT]; Exper. Math. 11 (2002), 437-446.
%H <a href="/index/Ed#EKG">Index entries for sequences related to EKG sequence</a>
%t ekg[s_List] := Block[{m = s[[-1]], k = 3}, While[MemberQ[s, k] || GCD[m, k] == 1, k++]; Append[s, k]]; A064413 = Nest[ekg, {1, 2}, 200];
%t Position[A064413, _?OddQ] // Flatten (* _Jean-François Alcover_, Aug 02 2018, after _Robert G. Wilson v_ *)
%o (Haskell)
%o import Data.List (findIndices)
%o a064957 n = a064957_list !! (n-1)
%o a064957_list = map (+ 1) $ findIndices odd a064413_list
%o -- _Reinhard Zumkeller_, Sep 17 2001
%Y Cf. A064413, A064473.
%Y Cf. A064955.
%K nonn
%O 1,2
%A _N. J. A. Sloane_, Oct 30 2001
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