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A051857
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Numbers n such that (n!)^2-n!+1 is prime.
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0
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OFFSET
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1,1
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COMMENTS
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a(1)-a(9) are verified primes using BLS option in pfgw. - Robert Price, Aug 24 2014
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LINKS
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PROG
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(PARI) isok(n) = isprime((n!)^2-n!+1); \\ Michel Marcus, Aug 26 2013
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CROSSREFS
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KEYWORD
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nonn,hard,more
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AUTHOR
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Andrew Walker (ajw01(AT)uow.edu.au), Dec 13 1999
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EXTENSIONS
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STATUS
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approved
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