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A093622
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Largest prime of the form n!/k!-1.
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1
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5, 23, 59, 719, 5039, 6719, 181439, 5039, 6652799, 479001599, 154439, 87178291199, 54486431999, 3487131647999, 59281238015999, 1067062284287999, 1013709170073599, 405483668029439999, 39070079, 180503769599
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OFFSET
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3,1
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LINKS
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EXAMPLE
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a(5) =59 because 5!/1!-1=119=7*17 is composite, whereas 5!/2!-1=59 is prime.
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PROG
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ECM, see link.
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CROSSREFS
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Cf. A093623 smallest k>0 such that n!/k!-1 is prime, A055490 primes of form n!-1, A093437 largest prime of the form n!/k!+1.
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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