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A242929 Primes p such that 2^p - p^2 is prime. 0
5, 7, 17, 19, 53, 83, 227, 461, 2221, 3547, 9029 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(12) > 23053. - Robert Israel, Jun 10 2014

LINKS

Table of n, a(n) for n=1..11.

EXAMPLE

5 is in this sequence because 5 and 2^5 - 5^2 = 7 are both prime.

MAPLE

select(p -> isprime(p) and isprime(2^p - p^2), {2} union {seq(2*i+1, i=1..2000)}); # Robert Israel, Jun 10 2014

MATHEMATICA

Select[Prime[Range[300]], PrimeQ[2^# - #^2] &] (* Alonso del Arte, May 27 2014 *)

PROG

(MAGMA) [p: p in PrimeUpTo(2200) | IsPrime(2^p - p^2)];

CROSSREFS

Cf. A098105.

Sequence in context: A196670 A075304 A168245 * A128490 A023519 A023517

Adjacent sequences:  A242926 A242927 A242928 * A242930 A242931 A242932

KEYWORD

nonn,more

AUTHOR

Juri-Stepan Gerasimov, May 27 2014

EXTENSIONS

a(9) from Alonso del Arte, May 27 2014

a(10) from Alois P. Heinz, May 28 2014

a(11) from Robert Israel, Jun 10 2014

STATUS

approved

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Last modified May 18 14:00 EDT 2021. Contains 343995 sequences. (Running on oeis4.)