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%I #12 Feb 18 2022 17:54:37
%S 2,3,19,31,59,67,71,79,103,107,127,151,167,179,211,223,227,307,331,
%T 379,383,431,439,487,523,547,563,599,607,659,683,743,751,787,811,827,
%U 839,863,887,907,911,971,983,991,1019,1039,1063,1091,1123,1171,1231,1283
%N Primes of the form 3*x^2 + 4*x*y - 5*y^2 (as well as of the form 3*x^2 + 10*x*y + 2*y^2).
%C Discriminant = 76. Class = 2. Binary quadratic forms a*x^2 + b*x*y + c*y^2 have discriminant d = b^2 - 4ac.
%D Z. I. Borevich and I. R. Shafarevich, Number Theory.
%H N. J. A. Sloane et al., <a href="/wiki/Binary_Quadratic_Forms_and_OEIS">Binary Quadratic Forms and OEIS</a>: Index to related sequences, programs, references. OEIS wiki, June 2014.
%H D. B. Zagier, <a href="https://doi.org/10.1007/978-3-642-61829-1">Zetafunktionen und quadratische Körper</a>, Springer, 1981.
%e a(4) = 31 because we can write 31 = 3*3^2 + 4*3*2 - 5*2^2 (or 31 = 3*1^2 + 10*1*2 + 2*2^2).
%Y Cf. A142956 (d=76). A038872 (d=5). A038873 (d=8). A068228, A141123 (d=12). A038883 (d=13). A038889 (d=17). A141111, A141112 (d=65).
%K nonn
%O 1,1
%A Laura Caballero Fernandez, Lourdes Calvo Moguer, Maria Josefa Cano Marquez, Oscar Jesus Falcon Ganfornina and Sergio Garrido Morales (laucabfer(AT)alum.us.es), Jul 14 2008
%E More terms from _Colin Barker_, Apr 05 2015
%E Edited by _M. F. Hasler_, Feb 18 2022
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