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Primes p such that 6*p^2+1 is also prime.
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%I #7 Sep 08 2022 08:45:40

%S 5,11,59,79,89,109,131,191,199,241,269,359,389,431,439,661,691,829,

%T 859,1019,1109,1181,1249,1319,1439,1621,1759,1789,1831,1949,1979,2011,

%U 2081,2111,2179,2341,2371,2389,2441,2459,2671,2699,2861,2999,3169,3229,3251

%N Primes p such that 6*p^2+1 is also prime.

%H Vincenzo Librandi, <a href="/A153812/b153812.txt">Table of n, a(n) for n = 1..1000</a>

%e For prime p = 199, 6*p^2+1 = 237607 is prime.

%t Select[Prime[Range[500]], PrimeQ[(6 #^2 + 1)]&] (* _Vincenzo Librandi_, Apr 14 2013 *)

%o (Magma) [ p: p in PrimesUpTo(3300) | IsPrime(6*p^2+1) ];

%Y Cf. A052291 (primes p such that 4p^2 + 1 is also prime).

%K nonn,easy

%O 1,1

%A _Klaus Brockhaus_, Jan 01 2009