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%I #18 Sep 08 2022 08:45:50
%S 5,17,59,89,167,269,467,719,1259,1949,2267,2609,2789,3167,3779,4217,
%T 4679,4919,5417,5939,7349,7649,9239,10979,11717,12479,14489,15767,
%U 16649,17099,18959,21419,21929,24029,25667,28517,31517,34667,35969,36629
%N Primes of the form 3*k^2 + 9*k + 5.
%C Primes of the form 12*k^2 + 18*k + 5. - _Charles R Greathouse IV_, Apr 13 2012
%H Jon E. Schoenfield, <a href="/A171838/b171838.txt">Table of n, a(n) for n = 1..10000</a>
%t Select[Table[3n^2+9n+5, {n,0,200}], PrimeQ] (* _Harvey P. Dale_, Jul 18 2014 *)
%o (PARI) for(n=0,99,if(isprime(t=12*n^2+18*n+5),print1(t", "))) \\ _Charles R Greathouse IV_, Apr 13 2012
%o (Magma) [3*n^2 +9*n +5: n in [0..250] | IsPrime(3*n^2 +9*n +5)]; // _G. C. Greubel_, Apr 29 2021
%o (Sage) [3*n^2 +9*n +5 for n in (0..250) if is_prime(3*n^2 +9*n +5)] # _G. C. Greubel_, Apr 29 2021
%Y Cf. A171748, A171749.
%K nonn,easy,less
%O 1,1
%A _Vladimir Joseph Stephan Orlovsky_, Dec 19 2009
%E Definition simplified by _Charles R Greathouse IV_, Apr 13 2012