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%I #5 May 13 2013 01:48:59
%S 3,4,5,6,7,8,80
%N Numbers n such that |n!-107| and |n!+107| are prime.
%F 5!-107=13 and 5!+107=227, so 5 is a member.
%t lst={};a=107;Do[If[PrimeQ[n!-a]&&PrimeQ[n!+a],AppendTo[lst,n]],{n,0,20^2}];lst
%o (PARI) for(n=1,106,if(ispseudoprime(abs(n!-107))&&ispseudoprime(n!+107),print1(n", "))) \\ _Charles R Greathouse IV_, Oct 05 2011
%K nonn,fini,full
%O 1,1
%A _Vladimir Joseph Stephan Orlovsky_, Sep 08 2008
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