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A261538
Primes p such that p^9 + 2 is also prime.
2
11, 41, 101, 227, 461, 587, 641, 887, 977, 1097, 1217, 1559, 2039, 2129, 2357, 3221, 3491, 3677, 3917, 4019, 4547, 5009, 5261, 5279, 5639, 6221, 6359, 6599, 6719, 7187, 7907, 8147, 9767, 9929, 10211, 10391, 11177, 11549, 11801, 11939, 12197, 12671, 13907
OFFSET
1,1
COMMENTS
All terms == 5 mod 6. Robert Israel, Aug 27 2015
LINKS
EXAMPLE
11 is in the sequence because 11^9 + 2 = 2357947693 is a prime.
MAPLE
select(t -> isprime(t) and isprime(t^9+2), [seq(6*i-1, i=1..10^4)]); # Robert Israel, Aug 27 2015
MATHEMATICA
Select[Prime[Range[2000]], PrimeQ[#^9 + 2] &]
PROG
(Magma) [p: p in PrimesUpTo(20000) | IsPrime(p^9+2)];
(PARI) forprime(p=2, 10^4, if (isprime(p^9+2), print1(p, ", "))) \\ Anders Hellström, Aug 27 2015
(PARI) list(lim)=my(v=List(), t); forprime(p=2, lim, if(isprime(p^9+2), listput(v, p))); Vec(v) \\ Charles R Greathouse IV, Aug 27 2015
CROSSREFS
Subsequence of A007528.
Cf. A000040.
Cf. similar sequences listed in A261536.
Sequence in context: A356260 A132208 A233434 * A066595 A260266 A195117
KEYWORD
nonn
AUTHOR
Vincenzo Librandi, Aug 24 2015
STATUS
approved