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Primes of the form 8x^2+21y^2.
2

%I #16 Sep 08 2022 08:45:34

%S 29,53,149,197,317,389,557,653,701,821,1061,1229,1373,1493,1709,1733,

%T 1877,1901,1997,2069,2213,2237,2333,2381,2549,2741,2837,2909,3221,

%U 3389,3413,3557,3581,3677,3917,4013,4229,4253,4349,4397,4421,4517

%N Primes of the form 8x^2+21y^2.

%C Discriminant=-672. See A139827 for more information.

%C Also primes of the form 29x^2+12xy+36y^2. See A140633. - _T. D. Noe_, May 19 2008

%H Vincenzo Librandi and Ray Chandler, <a href="/A139877/b139877.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)

%F The primes are congruent to {29, 53, 149} (mod 168).

%t QuadPrimes2[8, 0, 21, 10000] (* see A106856 *)

%o (Magma) [ p: p in PrimesUpTo(6000) | p mod 168 in {29, 53, 149}]; // _Vincenzo Librandi_, Jul 30 2012

%K nonn,easy

%O 1,1

%A _T. D. Noe_, May 02 2008