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%I #3 Mar 31 2012 10:29:09
%S 2,6,14,25,114,188,193,361,712,1767,3195,4995,5682,6485
%N Numbers n such that (2*n)!/n!-1 is prime.
%C Next term is > 9680.
%Y Cf. A112854 primes of the form (2*n)!/n!-1, 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, A112863 (2*n)!/(2*(n!)^2)+1 is prime.
%K hard,nonn
%O 1,1
%A _Hugo Pfoertner_, Sep 25 2005
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