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A095017 Number of lesser twin primes (A001359) in range ]2^n,2^(n+1)]. 0
1, 1, 1, 2, 2, 3, 7, 7, 12, 26, 45, 70, 113, 215, 355, 666, 1153, 2071, 3785, 6965, 12495, 22643, 41608, 76371, 140944, 261752, 484968, 904799, 1689477, 3160113, 5928904, 11139071, 20970782 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

COMMENTS

Conjecture: a(n) > 0 for all n. This holds for all n <= 100. - Charles R Greathouse IV, May 14 2012

LINKS

Table of n, a(n) for n=1..33.

A. Karttunen and J. Moyer, C-program for computing the initial terms of this sequence

Index entries for sequences related to occurrences of various subsets of primes in range ]2^n,2^(n+1)]

MATHEMATICA

Table[ps = Prime[Range[PrimePi[2^n] + 1, PrimePi[2^(n+1) + 1]]]; Count[Differences[ps], 2], {n, 25}] (* T. D. Noe, May 08 2012 *)

CROSSREFS

Cf. A095016, A036378.

Sequence in context: A068519 A108041 A259254 * A141559 A211395 A160433

Adjacent sequences:  A095014 A095015 A095016 * A095018 A095019 A095020

KEYWORD

nonn

AUTHOR

Antti Karttunen and Labos Elemer, Jun 01 2004

STATUS

approved

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Last modified November 12 09:29 EST 2019. Contains 329054 sequences. (Running on oeis4.)