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A162712
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Primes p such that 3^p-2^p-2 is also 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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The associated 3^p-2^p-2 are in A162713.
The list of k such that 3^k-2^k-2 is prime is: 2, 3, 43, 61, 63, 1369, ..., where 63 and 1369 are not prime.
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LINKS
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EXAMPLE
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2 is in the sequence because 3^2-2^2-2 = 3 is prime.
3 is in the sequence because 3^3-2^3-2 = 17 is prime.
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MAPLE
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a := proc(n) if isprime(n) and isprime(3^n-2^n-2) then n end if end proc:
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MATHEMATICA
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Select[Prime[Range[11000]], PrimeQ[3^# - 2^# - 2] &] (* Vincenzo Librandi, Sep 25 2015 *)
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PROG
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(PARI) forprime(p=2, 1e3, if (isprime(3^p-2^p-2), print1(p, ", "))) \\ Altug Alkan, Sep 25 2015
(Magma) [p: p in PrimesUpTo(1000) | IsPrime(3^p-2^p-2)]; // Vincenzo Librandi, Sep 26 2015
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CROSSREFS
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KEYWORD
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nonn,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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