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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
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
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
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