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A112863 Numbers n such that (2*n)!/(2*(n!)^2)+1 is prime. 5
1, 3, 5, 6, 14, 19, 24, 45, 49, 62, 72, 122, 149, 197, 209, 222, 349, 409, 491, 527, 601, 675, 728, 769, 795, 853, 1039, 1318, 1599, 2069, 2279, 2567, 2634, 3286, 3482, 6880, 6919, 9117, 9276, 9564, 10898, 13061, 14570 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..43.

CROSSREFS

Cf. A001700(n-1)=(2*n)!/(2*(n!)^2), A112864 primes of the form (2*n)!/(2*(n!)^2)+1, A112853 (2*n)!/n!-1 is prime, A112855 (2*n)!/n!+1 is prime, A066726 (2*n)!/(n!)^2-1 is prime, A112859 (2*n)!/(n!)^2+1 is prime, A112861 (2*n)!/(2*(n!)^2)-1 is prime.

Sequence in context: A048968 A185737 A092862 * A290964 A298563 A180694

Adjacent sequences:  A112860 A112861 A112862 * A112864 A112865 A112866

KEYWORD

hard,nonn

AUTHOR

Hugo Pfoertner, Sep 30 2005

EXTENSIONS

More terms from Charles R Greathouse IV, Sep 26 2006

STATUS

approved

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Last modified July 19 04:25 EDT 2019. Contains 325144 sequences. (Running on oeis4.)