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A076960
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a(n) is the number of primes between n! and (2n)!.
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0
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OFFSET
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1,2
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LINKS
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Table of n, a(n) for n=1..9.
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EXAMPLE
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a(2) = 8 as pi(24) = 9 and pi(2) = 1.
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MAPLE
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with(numtheory): 0, seq(pi((2*n)!)-pi(n!), n=2..5); # Emeric Deutsch, Jul 31 2005
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MATHEMATICA
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a[n_] := PrimePi[(2n)! - 1] - PrimePi[n! ]; Table[a[n], {n, 1, 8}] (* Ryan Propper, Sep 11 2005 *)
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CROSSREFS
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Cf. A076959.
Sequence in context: A215793 A273279 A227851 * A298623 A035130 A055762
Adjacent sequences: A076957 A076958 A076959 * A076961 A076962 A076963
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KEYWORD
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nonn
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AUTHOR
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Amarnath Murthy, Oct 21 2002
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EXTENSIONS
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Corrected and extended by Emeric Deutsch, Jul 31 2005
2 further terms from Ryan Propper, Sep 11 2005
a(9) from Donovan Johnson, Mar 10 2010
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STATUS
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approved
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