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Primes p such that 13*p^2+3*p+1 is a prime.
2

%I #10 Sep 08 2022 08:45:40

%S 2,3,7,11,13,19,23,37,41,47,53,73,79,97,107,163,167,211,223,227,229,

%T 317,337,347,353,389,397,419,491,499,547,569,601,677,683,727,757,829,

%U 839,941,1051,1117,1151,1163,1181,1201,1217,1367,1399,1409,1427,1433,1453

%N Primes p such that 13*p^2+3*p+1 is a prime.

%H Vincenzo Librandi, <a href="/A155153/b155153.txt">Table of n, a(n) for n = 1..1000</a>

%e For p=3, 13*p^2+3*p+1=127; p=73, 13*p^2+3*p+1=69497

%t Select[Prime[Range[1000]], PrimeQ[(13 #^2 + 3 # + 1)] &] (* _Vincenzo Librandi_, Oct 14 2012 *)

%o (Magma) [p: p in PrimesUpTo(1500) | IsPrime(13*p^2+3*p+1)]; // _Vincenzo Librandi_, Oct 14 2012

%Y Subsequence of A155152.

%K nonn,easy

%O 1,1

%A _Vincenzo Librandi_, Jan 21 2009