%I
%S 3,7,43,67,103,127,163,223,283,307,367,463,487,523,547,607,643,727,
%T 787,823,883,907,967,1063,1087,1123,1303,1327,1423,1447,1483,1543,
%U 1567,1627,1663,1723,1747,1783,1867,1987,2083,2143,2203,2287,2347,2383,2467,2503,2647,2683
%N Primes of the form 2*x^2+6*x*y+3*y^2 (as well as of the form 7*x^2+12*x*y+3*y^2).
%C Discriminant = 60. Class = 4. Binary quadratic forms a*x^2+b*x*y+c*y^2 have discriminant d=b^24ac and gcd(a,b,c)=1
%C This is also the list of primes p such that p = 3 or p is congruent to 7 or 43 mod 60.  _JeanFrançois Alcover_, Oct 28 2016
%D Z. I. Borevich and I. R. Shafarevich, Number Theory.
%D D. B. Zagier, Zetafunktionen und quadratische Koerper.
%H Juan AriasdeReyna, <a href="/A141304/b141304.txt">Table of n, a(n) for n = 1..10000</a>
%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)
%e a(3)=43 because we can write 43=2*1^2+6*1*3+3*3^2 (or 43=7*1^2+12*1*2+3*2^2).
%t Select[Prime[Range[500]], # == 3  MatchQ[Mod[#, 60], 743]&] (* _JeanFrançois Alcover_, Oct 28 2016 *)
%Y Cf. A107152, A141302, A141303 (d=60).
%Y Primes in A243190.
%K nonn
%O 1,1
%A Laura Caballero Fernandez, Lourdes Calvo Moguer, Maria Josefa Cano Marquez, Oscar Jesus Falcon Ganfornina and Sergio Garrido Morales (oscfalgan(AT)yahoo.es), Jun 24 2008
