%I #21 Aug 05 2014 14:16:29
%S 67,79,127,163,277,373,421,463,541,547,571,613,631,739,823,877,967,
%T 1009,1033,1051,1087,1093,1129,1213,1297,1579,1621,1663,1723,1831,
%U 1933,1999,2011,2179,2251,2269,2293,2377,2389,2437,2503,2557,2683,2689,2731,2767
%N Primes of the form x^2 - xy + 16y^2, with x and y nonnegative.
%C Discriminant = -63.
%C This appears to coincide with the sequence of primes of the form x^2 + 63y^2. - _Artur Jasinski_, Apr 24 2008
%H Vincenzo Librandi and Ray Chandler, <a href="/A106930/b106930.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 QuadPrimes2[1, -1, 16, 10000] (* see A106856 *)
%o (PARI) {a(n)= local(m,c,x); if(n<1, 0, c=0; m=1; while( c<n, m++; if( isprime(m), for(x=0,sqrtint(m\7), if(issquare(m-7*x^2), if( x%3==0, c++); break)))); m)} /* _Michael Somos_, May 28 2005 */
%K nonn,easy
%O 1,1
%A _T. D. Noe_, May 09 2005
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