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%I #18 Sep 08 2022 08:45:33
%S 3,43,67,163,283,307,523,547,643,787,883,907,1123,1483,1627,1723,1747,
%T 1867,1987,2083,2203,2347,2467,2683,2707,2803,3067,3163,3187,3307,
%U 3547,3643,3907,4003,4027,4243,4363,4483,4507,4603,4723,4987,5107
%N Primes of the form 3x^2 + 40y^2.
%C Discriminant=-480. See A139827 for more information.
%C Except for 3, also primes of the form 27x^2+12xy+28y^2. See A140633. - _T. D. Noe_, May 19 2008
%H Vincenzo Librandi and Ray Chandler, <a href="/A139854/b139854.txt">Table of n, a(n) for n = 1..10000</a> [First 1000 terms from Vincenzo Librandi]
%H N. J. A. Sloane et al., <a href="https://oeis.org/wiki/Binary_Quadratic_Forms_and_OEIS">Binary Quadratic Forms and OEIS</a> (Index to related sequences, programs, references)
%F Except for 3, the primes are congruent to {43, 67} (mod 120).
%t QuadPrimes2[3, 0, 40, 10000] (* see A106856 *)
%o (Magma) [3] cat [ p: p in PrimesUpTo(6000) | p mod 120 in {43, 67}]; // _Vincenzo Librandi_, Jul 29 2012
%o (PARI) list(lim)=my(v=List(),w,t); for(x=1, sqrtint(lim\3), w=3*x^2; for(y=0, sqrtint((lim-w)\40), if(isprime(t=w+40*y^2), listput(v,t)))); Set(v) \\ _Charles R Greathouse IV_, Feb 22 2017
%Y Cf. A140633.
%K nonn,easy
%O 1,1
%A _T. D. Noe_, May 02 2008
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