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A076960 a(n) is the number of primes between n! and (2n)!. 0
0, 8, 125, 4222, 258659, 25306159, 3610490130, 706003793908, 181035032176791 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..9.

EXAMPLE

a(2) = 8 as pi(24) = 9 and pi(2) = 1.

MAPLE

with(numtheory): 0, seq(pi((2*n)!)-pi(n!), n=2..5); # Emeric Deutsch, Jul 31 2005

MATHEMATICA

a[n_] := PrimePi[(2n)! - 1] - PrimePi[n! ]; Table[a[n], {n, 1, 8}] (* Ryan Propper, Sep 11 2005 *)

CROSSREFS

Cf. A076959.

Sequence in context: A215793 A273279 A227851 * A298623 A035130 A055762

Adjacent sequences:  A076957 A076958 A076959 * A076961 A076962 A076963

KEYWORD

nonn

AUTHOR

Amarnath Murthy, Oct 21 2002

EXTENSIONS

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

STATUS

approved

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Last modified May 21 21:43 EDT 2022. Contains 353929 sequences. (Running on oeis4.)