%I #12 Sep 02 2018 08:23:42
%S 3,5,4,6,8,5,4,6,14,4,6,7,7,8,11,7,8,13,6,4,13,9,7,15,7,8,6,4,9,20,17,
%T 6,5,15,8,10,8,9,14,8,8,19,8,6,4,20,19,10,8,6,14,4,12,13,14,9,7,13,10,
%U 9,8,24,6,12,7,23,10,16,9,6,11,18,8,17,6,6,20,10,15
%N Gaps between where primes occur in A064413.
%H T. D. Noe, <a href="/A064425/b064425.txt">Table of n, a(n) for n=1..1000</a>
%H 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], 2002.
%H J. C. Lagarias, E. M. Rains and N. J. A. Sloane, <a href="https://projecteuclid.org/euclid.em/1057777433">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 terms = 80;
%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, {2, 4}, 12 terms];
%t fp[n_] := FirstPosition[EKG, Prime[n]][[1]];
%t Array[fp, terms] // Differences (* _Jean-François Alcover_, Sep 02 2018, after _Robert G. Wilson v_ in A064413 *)
%Y Cf. A064413. First differences of A064955 and also of A064423.
%Y Cf. A137847.
%K nonn
%O 1,1
%A _N. J. A. Sloane_, Oct 01 2001