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%I A108519
%S A108519 11,271,6701
%N A108519 a(n) is the smallest natural number m such that (10^n)! - m is prime.
%C A108519 If a(n) is composite then a(n)>10^(2n)+2*10^n. Conjecture: All terms 
               are noncomposite numbers.
%e A108519 a(3)=6701 because (10^3)!-6701 is prime and for 0<m<6701 1000!-m is
%e A108519 composite.
%t A108519 a[n_] := (For[m = 1, ! PrimeQ[(10^n)! - m], m++ ]; m); Do[Print[a[n]], 
               {n, 3}]
%Y A108519 Cf. A108518.
%Y A108519 Sequence in context: A100841 A003389 A027019 this_sequence A160195 A062210 
               A049080
%Y A108519 Adjacent sequences: A108516 A108517 A108518 this_sequence A108520 A108521 
               A108522
%K A108519 more,nonn,bref
%O A108519 1,1
%A A108519 Farideh Firoozbakht (mymontain(AT)yahoo.com), Jul 10 2005

    
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Last modified December 6 19:58 EST 2009. Contains 170429 sequences.


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