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A072599
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Numbers n such that (n!)^2 - prime(n) is prime.
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1
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3, 4, 5, 6, 7, 16, 109, 116, 232, 877, 934
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OFFSET
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1,1
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COMMENTS
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Values associated with 16, 109, 116 and 232 certified prime with Primo. These primes have lengths 27, 353, 382 and 900 digits, respectively.
a(10)-a(11) associated with probable primes. - Robert Price, Aug 23 2014
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LINKS
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EXAMPLE
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(5!)^2 - prime(5) = 120^2 - 11 = 14400 - 11 = 14389 is prime, so 5 is a term.
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PROG
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(PARI) for(n=1, 800, if(isprime((n!)^2-prime(n)), print1(n, ", ")))
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CROSSREFS
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Cf. A064769 (n such that (n!)^2 + p(n) is prime).
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KEYWORD
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nonn,more,hard
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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