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A088110
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Numbers n such that 2^n + n and 2^n - n are noncomposite.
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0
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OFFSET
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1,3
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COMMENTS
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Conjecture: sequence is finite.
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LINKS
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EXAMPLE
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9 is a member as 2^9 + 9 = 521 and 2^9 - 9 = 503 are primes.
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MATHEMATICA
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Join[{0, 1}, Select[Range[1000], PrimeQ[2^# + #] && PrimeQ[2^# -#] &]] (* Vincenzo Librandi, Dec 08 2015 *)
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PROG
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(Magma) [0, 1] cat [n: n in [0..1000] | IsPrime(2^n+n) and IsPrime(2^n-n)]; // Vincenzo Librandi, Dec 08 2015
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CROSSREFS
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KEYWORD
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more,nonn
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AUTHOR
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STATUS
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approved
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