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A100600
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Numbers k such that (prime(k)-1)! + prime(k)^6 is prime.
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2
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OFFSET
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1,1
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COMMENTS
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k = {3, 4, 29, 32, 133} yields primes p(n) = {5, 7, 109, 131, 751}. There are no more such k up to k=100. Computed in collaboration with Ray Chandler.
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LINKS
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FORMULA
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Numbers k such that (prime(k)-1)! + prime(k)^6 is prime, where prime(k) is the k-th prime.
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EXAMPLE
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a(1) = 3 because (prime(3)-1)! + prime(3)^6 = (5-1)! + 5^6 = 15649 is the smallest prime of that form.
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MATHEMATICA
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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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EXTENSIONS
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STATUS
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approved
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