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 A093981 Number of prime pairs below 10^n having a difference of 54. 2
 0, 0, 0, 0, 4, 140, 2403, 33593, 410754, 4627165, 49484726, 511589763, 5167085638, 51359117940, 504751212449, 4920758221226, 47694473239363, 460356869024451 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,5 COMMENTS The primes must be consecutive, i.e., there must be no other primes between p and (p+54). - Harvey P. Dale, Aug 08 2011 LINKS Siegfried "Zig" Herzog, Frequency of Occurrence of Prime Gaps T. Oliveira e Silva, S. Herzog, and S. Pardi, Empirical verification of the even Goldbach conjecture and computation of prime gaps up to 4.10^18, Math. Comp., 83 (2014), 2033-2060. EXAMPLE a(6) = 140 because there are 140 prime gaps of 54 below 10^6. MATHEMATICA Table[Count[Partition[Prime[Range[PrimePi[10^i]]], 2, 1], _?(Last[#] - First[#] == 54&)], {i, 9}] (* Harvey P. Dale, Aug 08 2011 *) CROSSREFS Cf. A007508, A093980, A093982. Sequence in context: A221675 A340838 A291450 * A055304 A270065 A002917 Adjacent sequences: A093978 A093979 A093980 * A093982 A093983 A093984 KEYWORD nonn,more AUTHOR Enoch Haga, Apr 24 2004 EXTENSIONS a(10)-a(13) from Washington Bomfim, Jun 22 2012 a(14)-a(18) from S. Herzog's website added by Giovanni Resta, Aug 14 2018 STATUS approved

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Last modified March 30 19:10 EDT 2023. Contains 361622 sequences. (Running on oeis4.)