|
| |
|
|
A076960
|
|
Number of primes between n! and (2n)!.
|
|
0
| | |
|
|
|
OFFSET
| 1,2
|
|
|
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); (Deutsch)
|
|
|
MATHEMATICA
| a[n_] := PrimePi[(2n)! - 1] - PrimePi[n! ]; Table[a[n], {n, 1, 8}] (Propper)
|
|
|
CROSSREFS
| Cf. A076959.
Sequence in context: A061103 A110272 A033536 * A035130 A055762 A029472
Adjacent sequences: A076957 A076958 A076959 * A076961 A076962 A076963
|
|
|
KEYWORD
| nonn
|
|
|
AUTHOR
| Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Oct 21 2002
|
|
|
EXTENSIONS
| Corrected and extended by Emeric Deutsch (deutsch(AT)duke.poly.edu), Jul 31 2005
2 further terms from Ryan Propper (rpropper(AT)stanford.edu), Sep 11 2005
a(9) from Donovan Johnson (donovan.johnson(AT)yahoo.com), Mar 10 2010
|
| |
|
|
