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A057665
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Numbers k such that prime(k) + 2^prime(k) is prime.
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3
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OFFSET
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1,1
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COMMENTS
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These values correspond to indices ip = 2, 3, 9, 10, 11 where A052007(ip) is prime. - Michel Marcus, Dec 20 2013
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LINKS
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FORMULA
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MATHEMATICA
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PROG
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(PARI) isok(n) = isprime(prime(n) + 2^prime(n)); \\ Michel Marcus, Dec 19 2013
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CROSSREFS
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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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