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A175173 Primes p such that 2^p+5 is also prime. 1
3, 5, 11, 47, 53, 191, 34763 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(8) > 5*10^5. - Robert Price, Sep 18 2015

LINKS

Table of n, a(n) for n=1..7.

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

Adjacent sequences:  A175170 A175171 A175172 * A175174 A175175 A175176

KEYWORD

nonn

AUTHOR

Vincenzo Librandi, Mar 09 2010

EXTENSIONS

a(7) from Robert Price, Sep 18 2015

STATUS

approved

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Last modified December 7 22:50 EST 2021. Contains 349590 sequences. (Running on oeis4.)