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%I #12 Sep 08 2022 08:45:29
%S 2,17,23,29,31,43,47,53,59,61,67,71,89,97,109,113,127,131,137,157,163,
%T 173,179,181,193,197,199,211,223,229,239,241,257,263,271,277,281,283,
%U 293,307,313,317,331,347,349,353,359,367,373,379,383,389,397,401,409
%N Primes p such that (3p)^2 + 2 is not prime.
%D Garath A. Jones and Mary Jones, Elementary Number Theory, Springer - Verlag London, 1998; p. 35, Exercise 2.17.
%H Vincenzo Librandi, <a href="/A126961/b126961.txt">Table of n, a(n) for n = 1..1000</a>
%t Select[Prime[Range[100]], ! PrimeQ[(3#)^2 + 2] &] (* _Harvey P. Dale_, Jun 14 2011 *)
%o (PARI) g(n) = forprime(x=0,n,y=9*x^2+2;if(!isprime(y),print1(x",")))
%o (Magma) [p: p in PrimesUpTo(500) | not IsPrime(9*p^2+2)]; // _Vincenzo Librandi_, Apr 17 2013
%K nonn,easy
%O 1,1
%A _Cino Hilliard_, Mar 19 2007
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