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A175173
Primes p such that 2^p+5 is also prime.
1
3, 5, 11, 47, 53, 191, 34763
OFFSET
1,1
COMMENTS
a(8) > 5*10^5. - Robert Price, Sep 18 2015
FORMULA
A000040 INTERSECT A059242. [R. J. Mathar, May 02 2010]
EXAMPLE
For p=3, 2^3+5=13; p=5, 2^5+5=37; p=11, 2^11+5=2053
MATHEMATICA
Select[Prime@ Range@ 1000, PrimeQ[2^# + 5] &] (* Michael De Vlieger, Sep 18 2015 *)
PROG
(Magma) [p: p in PrimesUpTo(7000) | IsPrime(2^p+5) ]
CROSSREFS
Sequence in context: A144467 A049883 A059242 * A268510 A004203 A201473
KEYWORD
nonn
AUTHOR
Vincenzo Librandi, Mar 09 2010
EXTENSIONS
a(7) from Robert Price, Sep 18 2015
STATUS
approved