%I #9 Feb 13 2019 08:02:39
%S 1,3,9,5,15,7,21,11,33,27,25,35,13,39,17,51,19,57,45,23,69,49,63,55,
%T 65,29,87,31,93,37,111,75,41,123,81,77,43,129,85,95,47,141,91,99,105,
%U 53,159,59,177,117,115,125,61,183,119,133,121,143,67,201
%N The odd subsequence of A064413.
%H J. C. Lagarias, E. M. Rains and N. J. A. Sloane, <a href="http://arXiv.org/abs/math.NT/0204011">The EKG sequence</a>, Exper. Math. 11 (2002), 437-446.
%H <a href="/index/Ed#EKG">Index entries for sequences related to EKG sequence</a>
%t nmax = 140;
%t ekg[s_] := Block[{m = s[[-1]], k = 3}, While[MemberQ[s, k] || GCD[m, k] == 1, k++]; Append[s, k]];
%t EKG = Nest[ekg, {1, 2}, nmax];
%t Select[EKG, OddQ] (* _Jean-François Alcover_, Feb 13 2019, after _Robert G. Wilson v_ in A064413 *)
%Y Cf. A064413.
%K nonn
%O 1,2
%A _N. J. A. Sloane_, Oct 05 2001