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A112864
Primes of the form (2*n)!/(2*(n!)^2)+1.
2
2, 11, 127, 463, 20058301, 17672631901, 16123801841551, 51913710643776705684835561, 12738806129490428451365214301, 760401738905937245009910944207609329, 740106499224393094996908447741294397438051
OFFSET
1,1
MATHEMATICA
Select[Table[(2n)!/(2(n!)^2)+1, {n, 70}], PrimeQ] (* Harvey P. Dale, Feb 28 2023 *)
CROSSREFS
Cf. A001700(n-1)=(2*n)!/(2*(n!)^2), A112863 gives n such that (2*n)!/(2*(n!)^2)+1 is prime, A112862 gives primes of the form (2*n)!/(2*(n!)^2)-1.
Sequence in context: A279703 A206401 A193207 * A077391 A104087 A208858
KEYWORD
nonn
AUTHOR
Hugo Pfoertner, Sep 30 2005
STATUS
approved