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%I #4 Mar 30 2012 17:37:43
%S 11,271,6701
%N a(n) is the smallest natural number m such that (10^n)! - m is prime.
%C If a(n) is composite then a(n)>10^(2n)+2*10^n. Conjecture: All terms are noncomposite numbers.
%e a(3)=6701 because (10^3)!-6701 is prime and for 0<m<6701 1000!-m is
%e composite.
%t a[n_] := (For[m = 1, ! PrimeQ[(10^n)! - m], m++ ]; m); Do[Print[a[n]], {n, 3}]
%Y Cf. A108518.
%K more,nonn,bref
%O 1,1
%A _Farideh Firoozbakht_, Jul 10 2005
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