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A064473
Where the odd terms appear in A064413 (if it begins at 2).
2
4, 5, 9, 10, 13, 14, 19, 20, 21, 23, 24, 27, 28, 32, 33, 36, 37, 38, 42, 43, 49, 50, 52, 53, 56, 57, 60, 61, 66, 67, 68, 73, 74, 75, 77, 80, 81, 83, 84, 88, 89, 92, 95, 96, 99, 100, 106, 107, 108, 110, 111, 114, 115, 117, 118, 123, 124, 127, 128
OFFSET
1,1
LINKS
J. C. Lagarias, E. M. Rains and N. J. A. Sloane, The EKG sequence, arXiv:math/0204011 [math.NT], 2002; Exper. Math. 11 (2002), 437-446.
MATHEMATICA
ekg[s_] := Block[{m = s[[-1]], k = 3}, While[MemberQ[s, k] || GCD[m, k] == 1, k++]; Append[s, k]];
EKG = Nest[ekg, {1, 2}, 200] // Rest;
Position[EKG, _?OddQ] // Flatten (* Jean-François Alcover, Feb 07 2019, after Robert G. Wilson v in A064413 *)
CROSSREFS
Cf. A064413. See A064957 for better version.
Sequence in context: A008935 A003995 A380175 * A385609 A394621 A287962
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Oct 05 2001
STATUS
approved