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A084914
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Numbers k such that k^k*k! - 1 is prime.
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1
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OFFSET
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1,1
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COMMENTS
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a(1)-a(8) have been proved to correspond to primes. No other terms less than 10000. - Robert Price, May 19 2012
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LINKS
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EXAMPLE
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4 is in the sequence because 4!*4^4 - 1 = 6143 is prime.
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MATHEMATICA
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Do[If[PrimeQ[n^n*n!-1], Print[n]], {n, 700}]
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CROSSREFS
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KEYWORD
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more,hard,nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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