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 A141172 #28 Feb 18 2022 15:28:36
%S A141172 2,29,37,53,109,113,137,149,193,197,233,277,281,317,337,373,389,401,
%T A141172 421,449,457,541,557,569,613,617,641,653,673,701,709,757,809,821,877,
%U A141172 953,977,1009,1033,1061,1093,1117,1129,1201,1213,1229,1289,1297,1373,1381,1409,1429,1453,1481,1493
%N A141172 Primes of the form 2*x^2+2*x*y-3*y^2 (as well as of the form 2*x^2+6*x*y+y^2).
%C A141172 Discriminant = 28. Class = 2. Binary quadratic forms a*x^2+b*x*y+c*y^2 have discriminant d=b^2-4ac and gcd(a,b,c)=1.
%C A141172 Also, primes of form u^2-7v^2. The transformation {u,v}={3x+y,x} yields the second quadratic form given in the title. - _Tito Piezas III_, Dec 28 2008
%C A141172 This is also the list of primes p such that p = 2 or p is congruent to 1, 9 or 25 mod 28 - _Jean-François Alcover_, Oct 28 2016
%D A141172 Z. I. Borevich and I. R. Shafarevich, Number Theory.
%H A141172 Juan Arias-de-Reyna, <a href="/A141172/b141172.txt">Table of n, a(n) for n = 1..10000</a>
%H A141172 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 A141172 D. B. Zagier, <a href="https://doi.org/10.1007/978-3-642-61829-1">Zetafunktionen und quadratische Körper</a>, Springer, 1981.
%e A141172 a(2)=29 because we can write 29=2*4^2+2*4*3-3*3^2 (or 29=2*1^2+6*1*3+3^2).
%t A141172 Select[Prime[Range[250]], # == 2 || MatchQ[Mod[#, 28], 1|9|25]&] (* _Jean-François Alcover_, Oct 28 2016 *)
%Y A141172 Cf. A141173 (d=28) A038872 (d=5). A038873 (d=8). A068228, A141123 (d=12). A038883 (d=13). A038889 (d=17): A141111, A141112 (d=65).
%Y A141172 Cf. also A242662.
%Y A141172 For a list of sequences giving numbers and/or primes represented by binary quadratic forms, see the "Binary Quadratic Forms and OEIS" link.
%K A141172 nonn
%O A141172 1,1
%A A141172 Laura Caballero Fernandez, Lourdes Calvo Moguer, Maria Josefa Cano Marquez, Oscar Jesus Falcon Ganfornina and Sergio Garrido Morales (marcanmar(AT)alum.us.es), Jun 12 2008