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A064953 Where the even terms appear in A064413. 5
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, 47, 48, 49, 52, 55, 56, 59, 60, 63, 64, 65, 66, 70, 71, 72, 73, 77, 79, 80, 83, 86, 87, 88, 91, 92, 94, 95, 98, 99, 102, 103, 104, 105, 106, 110, 113, 114 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Complement of A064957; A195376(a(n)) = 0. [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.

Index entries for sequences related to EKG sequence

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, _?EvenQ] // Flatten (* Jean-Fran├žois Alcover, Aug 02 2018, after Robert G. Wilson v *)

PROG

(Haskell)

import Data.List (findIndices)

a064953 n = a064953_list !! (n-1)

a064953_list = map (+ 1) $ findIndices even a064413_list

-- Reinhard Zumkeller, Sep 17 2001

CROSSREFS

Cf. A064413, A064472 for better version.

Sequence in context: A105941 A276876 A047202 * A097503 A030701 A305924

Adjacent sequences:  A064950 A064951 A064952 * A064954 A064955 A064956

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Oct 30 2001

STATUS

approved

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Last modified November 22 08:33 EST 2019. Contains 329389 sequences. (Running on oeis4.)