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%I #19 Sep 08 2022 08:45:20
%S 1,3,5,7,11,19,21,25,31,33,37,39,45,49,53,73,75,77,81,89,91,93,107,
%T 115,119,129,131,135,137,145,157,185,187,193,203,205,207,213,215,221,
%U 227,229,231,249,259,261,263,271,283,291,297,299,301,317,325,327,331
%N Numbers n such that 3*n^2 + 4 is prime.
%H Harvey P. Dale, <a href="/A111052/b111052.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n) = sqrt(A201477(n)-4)/3)). - _Zak Seidov_, Feb 04 2016
%e If n=77 then 3*n^2 + 4 = 17791 (prime).
%t Select[Range[340], PrimeQ[3*#^2 + 4] &] (* _Stefan Steinerberger_, Feb 26 2006 *)
%o (PARI) lista(nn) = {for(n=1, nn, if(ispseudoprime(3*n^2 + 4), print1(n, ", ")));} \\ _Altug Alkan_, Feb 05 2016
%o (Magma) [n: n in [1..350] | IsPrime(3*n^2+4)]; // _Vincenzo Librandi_, Feb 06 2016
%Y Cf. A201477.
%K nonn
%O 1,2
%A _Parthasarathy Nambi_, Oct 06 2005
%E More terms from _Stefan Steinerberger_, Feb 26 2006
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