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A262098
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Primes p such that 2^p + 9 is also prime.
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5
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2, 3, 5, 7, 23, 37, 47, 263, 317, 3229, 3253
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OFFSET
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1,1
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COMMENTS
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LINKS
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EXAMPLE
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5 is in sequence because 2^5 + 9 = 41 is prime.
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MATHEMATICA
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Select[Prime[Range[1000]], PrimeQ[2^# + 9] &]
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PROG
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(Magma) [p: p in PrimesUpTo(1000) | IsPrime(2^p+9)];
(PARI) for(n=1, 1e3, if(isprime((2^prime(n))+9), print1(prime(n)", "))) \\ Altug Alkan, Sep 18 2015
(Perl) use ntheory ":all"; use Math::GMP qw/:constant/; forprimes { say if is_prime(2**$_+9) } 10000; # Dana Jacobsen, Oct 03 2015
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CROSSREFS
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Cf. primes p such that 2^p+k is a prime: A057736 (k=3), A175173 (k=5), this sequence (k=9), A155780 (k=11), A175234 (k=15), A262099 (k=17), A175235 (k=21), A175236 (k=23), A262934 (k=27), A262100 (k=29), A262201 (k=33), A262962 (k=35).
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KEYWORD
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nonn,more
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AUTHOR
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STATUS
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approved
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