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 A064957 Where the odd terms appear in A064413. 6
 1, 5, 6, 10, 11, 14, 15, 20, 21, 22, 24, 25, 28, 29, 33, 34, 37, 38, 39, 43, 44, 50, 51, 53, 54, 57, 58, 61, 62, 67, 68, 69, 74, 75, 76, 78, 81, 82, 84, 85, 89, 90, 93, 96, 97, 100, 101, 107, 108, 109, 111, 112, 115, 116, 118, 119, 124, 125, 128, 129 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Complement of A064953; A195376(a(n)) = 1. [Reinhard Zumkeller, Sep 17 2001] LINKS Reinhard Zumkeller, Table of n, a(n) for n = 1..10000 J. C. Lagarias, E. M. Rains and N. J. A. Sloane, The EKG sequence, arXiv:math/0204011 [math.NT]; Exper. Math. 11 (2002), 437-446. MATHEMATICA 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]; Position[A064413, _?OddQ] // Flatten (* Jean-François Alcover, Aug 02 2018, after Robert G. Wilson v *) PROG (Haskell) import Data.List (findIndices) a064957 n = a064957_list !! (n-1) a064957_list = map (+ 1) \$ findIndices odd a064413_list -- Reinhard Zumkeller, Sep 17 2001 CROSSREFS Cf. A064413, A064473. Cf. A064955. Sequence in context: A163903 A074627 A067612 * A008851 A079259 A275018 Adjacent sequences:  A064954 A064955 A064956 * A064958 A064959 A064960 KEYWORD nonn AUTHOR N. J. A. Sloane, Oct 30 2001 STATUS approved

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Last modified June 15 21:17 EDT 2021. Contains 345050 sequences. (Running on oeis4.)