A153591 - OEIS

%I #8 Sep 08 2022 08:45:40

%S 2,3,5,7,13,19,23,31,41,43,47,67,73,97,101,107,109,137,151,199,233,

%T 239,241,251,263,283,317,331,337,353,359,379,383,419,421,431,439,449,

%U 463,541,569,571,577,601,619,647,691,701,769,823,839,877,907,929,953,971

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

%H Vincenzo Librandi, <a href="/A153591/b153591.txt">Table of n, a(n) for n = 1..1000</a>

%e For p = 2, 6p^2+6p+1 = 37 is prime; for p = 47, 6p^2+6p+1 = 13537 is prime.

%t Select[Prime[Range[200]], PrimeQ[6#^2 + 6# + 1] &] (* _Vincenzo Librandi_, Oct 15 2012 *)

%o (Magma) [ p: p in PrimesUpTo(1000) | IsPrime(6*p^2+6*p+1) ];

%Y Cf. A007693 (n and 6n+1 are primes), A153812 (primes p such that 6*p^2+1 is also prime).

%K nonn,easy

%O 1,1

%A _Vincenzo Librandi_, Dec 29 2008

%E Edited and extended beyond a(20) by _Klaus Brockhaus_, Jan 01 2009