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A108519
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a(n) is the smallest natural number m such that (10^n)! - m is prime.
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1
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OFFSET
| 1,1
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COMMENTS
| If a(n) is composite then a(n)>10^(2n)+2*10^n. Conjecture: All terms are noncomposite numbers.
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EXAMPLE
| a(3)=6701 because (10^3)!-6701 is prime and for 0<m<6701 1000!-m is
composite.
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MATHEMATICA
| a[n_] := (For[m = 1, ! PrimeQ[(10^n)! - m], m++ ]; m); Do[Print[a[n]], {n, 3}]
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CROSSREFS
| Cf. A108518.
Sequence in context: A003389 A027019 A168147 * A160195 A203240 A062210
Adjacent sequences: A108516 A108517 A108518 * A108520 A108521 A108522
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KEYWORD
| more,nonn,bref
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AUTHOR
| Farideh Firoozbakht (mymontain(AT)yahoo.com), Jul 10 2005
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