%I #23 Aug 05 2014 14:16:29

%S 7,37,43,109,151,193,211,331,337,379,457,487,499,673,709,751,757,883,

%T 907,919,991,1117,1171,1201,1303,1327,1381,1423,1429,1453,1471,1549,

%U 1597,1747,1759,1789,1801,1873,2017,2053,2083,2137,2143,2221,2311,2347

%N Primes of the form 4x^2 + xy + 4y^2, with x and y any integer.

%C Discriminant = -63.

%H Vincenzo Librandi and Ray Chandler, <a href="/A106924/b106924.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)

%t Union[QuadPrimes2[4, 1, 4, 10000], QuadPrimes2[4, -1, 4, 10000]] (* see A106856 *)

%o (PARI) {a(n)= local(m,c,x,y); if(n<1, 0, c=0; m=1; while( c<n, m++; if( kronecker(m,7)!>=0&isprime(m), for(x=0,sqrtint(m\7), if(issquare(m-7*x^2,&y), if( y%3==0, c++); break)))); m)} /* _Michael Somos_, May 28 2005 */

%K nonn,easy

%O 1,1

%A _T. D. Noe_, May 09 2005