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A092751 Primes of the form (2*n)!/(n!)^2 - 1. 2
5, 19, 251, 48619, 155117519, 30067266499541039, 6637553085023755473070799, 399608854866744452032002440111, 5717214010165655645594487649236004008072121335004636113518216597999 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

MATHEMATICA

Binomial[2#, # ] - 1 & /@ Select[ Range[150], PrimeQ[(2#)!/#!^2 - 1] &] (* Robert G. Wilson v, Apr 14 2004 *)

CROSSREFS

Cf. A000984, A066726.

Cf. A075840 = n such that (2*n)!/(n!)^2-1 is prime, A112860 = primes of the form (2*n)!/(n!)^2+1.

Sequence in context: A317340 A328716 A067967 * A122150 A092663 A072526

Adjacent sequences:  A092748 A092749 A092750 * A092752 A092753 A092754

KEYWORD

nonn

AUTHOR

Jorge Coveiro, Apr 12 2004

EXTENSIONS

Corrected and extended by Robert G. Wilson v, Apr 14 2004

STATUS

approved

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Last modified July 11 20:03 EDT 2020. Contains 335652 sequences. (Running on oeis4.)