OFFSET
1,1
COMMENTS
a(8) > 5*10^5. - Robert Price, Sep 18 2015
FORMULA
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
KEYWORD
nonn
AUTHOR
Vincenzo Librandi, Mar 09 2010
EXTENSIONS
a(7) from Robert Price, Sep 18 2015
STATUS
approved