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A064425 Gaps between where primes occur in A064413. 4
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, 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, 9, 8, 24, 6, 12, 7, 23, 10, 16, 9, 6, 11, 18, 8, 17, 6, 6, 20, 10, 15 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

T. D. Noe, Table of n, a(n) for n=1..1000

J. C. Lagarias, E. M. Rains and N. J. A. Sloane, The EKG sequence, arXiv:math/0204011 [math.NT], 2002.

J. C. Lagarias, E. M. Rains and N. J. A. Sloane, The EKG sequence, Exper. Math. 11 (2002), 437-446.

Index entries for sequences related to EKG sequence

MATHEMATICA

terms = 80;

ekg[s_] := Block[{m = s[[-1]], k = 3}, While[MemberQ[s, k] || GCD[m, k] == 1, k++]; Append[s, k]];

EKG = Nest[ekg, {2, 4}, 12 terms];

fp[n_] := FirstPosition[EKG, Prime[n]][[1]];

Array[fp, terms] // Differences (* Jean-Fran├žois Alcover, Sep 02 2018, after Robert G. Wilson v in A064413 *)

CROSSREFS

Cf. A064413. First differences of A064955 and also of A064423.

Cf. A137847.

Sequence in context: A200324 A063259 A333717 * A094761 A114748 A182733

Adjacent sequences:  A064422 A064423 A064424 * A064426 A064427 A064428

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Oct 01 2001

STATUS

approved

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Last modified July 24 17:43 EDT 2021. Contains 346273 sequences. (Running on oeis4.)