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A238011
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Numbers n such that (2n)! - n! - 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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No more terms up to 5000. The first six terms are as previously stated in A118813. All terms found and primes proved by OpenPFGW.
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LINKS
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EXAMPLE
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5 is a term because (2*5)! - 5! - 1 = 3628679 is prime.
4039 is a term because (2*4039)! - 4039! - 1 is prime (28058 digits).
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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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STATUS
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approved
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