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A064953 Where the even terms appear in A064413.

%I A064953 #18 Aug 02 2018 02:37:13
%S A064953 2,3,4,7,8,9,12,13,16,17,18,19,23,26,27,30,31,32,35,36,40,41,42,45,46,
%T A064953 47,48,49,52,55,56,59,60,63,64,65,66,70,71,72,73,77,79,80,83,86,87,88,
%U A064953 91,92,94,95,98,99,102,103,104,105,106,110,113,114
%N A064953 Where the even terms appear in A064413.
%C A064953 Complement of A064957; A195376(a(n)) = 0. [_Reinhard Zumkeller_, Sep 17 2001]
%H A064953 Reinhard Zumkeller, <a href="/A064953/b064953.txt">Table of n, a(n) for n = 1..10000</a>
%H A064953 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 A064953 <a href="/index/Ed#EKG">Index entries for sequences related to EKG sequence</a>
%t A064953 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 A064953 Position[A064413, _?EvenQ] // Flatten (* _Jean-François Alcover_, Aug 02 2018, after _Robert G. Wilson v_ *)
%o A064953 (Haskell)
%o A064953 import Data.List (findIndices)
%o A064953 a064953 n = a064953_list !! (n-1)
%o A064953 a064953_list = map (+ 1) $ findIndices even a064413_list
%o A064953 -- _Reinhard Zumkeller_, Sep 17 2001
%Y A064953 Cf. A064413, A064472 for better version.
%K A064953 nonn
%O A064953 1,1
%A A064953 _N. J. A. Sloane_, Oct 30 2001