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A155778
Primes p such that 2^p + p + 6 is also prime.
0
3, 5, 23, 83, 239, 66029
OFFSET
1,1
COMMENTS
a(6), if it exists, is greater than 20000. - Dmitry Kamenetsky, Feb 06 2009
a(7), if it exists, is greater than 300000. - Michael S. Branicky, Sep 30 2024
MATHEMATICA
Select[Prime[Range[1000]], PrimeQ[(2^# + # + 6)]&] (* Vincenzo Librandi, Oct 30 2012 *)
PROG
(Magma) [p: p in PrimesUpTo(1000)| IsPrime(2^p + p +6)]; // Vincenzo Librandi, Oct 30 2012
CROSSREFS
Sequence in context: A066411 A153410 A230080 * A209028 A178068 A018978
KEYWORD
nonn,more
AUTHOR
Vincenzo Librandi, Jan 27 2009
EXTENSIONS
a(5) from Dmitry Kamenetsky, Feb 06 2009
a(6) from Michael S. Branicky, Jan 30 2023
STATUS
approved