This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A243706 #10 Jun 20 2014 04:50:29
%S A243706 3,7,13,17,47,53,67,97,137,157,167,193,227,233,257,263,293,313,317,
%T A243706 347,383,397,457,463,503,547,557,563,577,587,593,643,653,673,683,727,
%U A243706 757,773,823,827,883,887,937,967,977,997,1013,1063,1093
%N A243706 Primes represented by the indefinite quadratic form 3x^2+13xy-3y^2.
%C A243706 Discriminant 205.
%C A243706 12*a(n) has the form z^2 - 205*y^2, where z = 6*x+13*y. [_Bruno Berselli_, Jun 20 2014]
%H A243706 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)
%o A243706 (PARI)
%o A243706 fc(a,b,c,M) = {
%o A243706 my(t1=List(),t2);
%o A243706 forprime(p=2,prime(M),
%o A243706 t2 = qfbsolve(Qfb(a,b,c),p);
%o A243706 if(t2 != 0, listput(t1,p))
%o A243706 );
%o A243706 Vec(t1)
%o A243706 };
%o A243706 fc(3,13,-3,600)
%Y A243706 Primes in A243705.
%K A243706 nonn
%O A243706 1,1
%A A243706 _N. J. A. Sloane_, Jun 17 2014