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A122719
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Primes p such that (2p)!! - 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(n) are the primes from A091415[n] = {2,3,4,8,13,32,41,45,59,97,107,364,421,...} Numbers n such that n!*2^n - 1 is prime. Corresponding primes of the form (2p)!! - 1 are {3,5,270269,26226140915375977206881249, 58431212742946338570036120182498518593749,...}
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LINKS
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MATHEMATICA
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Select[Prime[Range[651]], PrimeQ[(2#)!!-1]&]
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CROSSREFS
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KEYWORD
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hard,more,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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