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A237814 Primes p such that 2*p+1 and 2*p+19 are also prime.

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%I A237814 #10 Sep 08 2022 08:46:06
%S A237814 2,5,11,41,89,131,191,251,419,431,641,809,1031,1229,1409,1439,1511,
%T A237814 1559,1601,1889,1901,1931,2069,2351,2399,2459,2699,2741,2819,2939,
%U A237814 3359,3449,3491,3761,3779,3911,4409,4919,5081,5849,6131,6449,6491,6551,7079,7151
%N A237814 Primes p such that 2*p+1 and 2*p+19 are also prime.
%H A237814 Vincenzo Librandi, <a href="/A237814/b237814.txt">Table of n, a(n) for n = 1..1000</a>
%e A237814 11 is in the sequence because 11, 2*11+1 = 23 and 2*11+19 = 41 are all prime.
%t A237814 Select[Prime[Range[8000]], PrimeQ[2 # + 1] && PrimeQ[2 # + 19] &] (* _Vincenzo Librandi_, Feb 15 2014 *)
%o A237814 (PARI) s=[]; forprime(p=2, 10000, if(isprime(2*p+1) && isprime(2*p+19), s=concat(s, p))); s
%o A237814 (Magma) [p: p in PrimesUpTo(8000) | IsPrime(2*p+1) and IsPrime(2*p+19)]; // _Vincenzo Librandi_, Feb 15 2014
%Y A237814 Cf. A126107, A237810, A237811, A237812, A237813.
%K A237814 nonn
%O A237814 1,1
%A A237814 _Colin Barker_, Feb 13 2014