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Primes of the form 4x^2+4xy+23y^2.
1

%I #20 Sep 08 2022 08:45:33

%S 23,31,47,71,103,191,199,223,311,367,383,463,487,599,631,647,719,727,

%T 751,823,839,863,911,983,991,1039,1087,1103,1279,1303,1367,1423,1439,

%U 1511,1543,1567,1607,1783,1831,1871,1879,1951,2039,2143,2311,2399

%N Primes of the form 4x^2+4xy+23y^2.

%C Discriminant=-352. See A139827 for more information.

%H Vincenzo Librandi and Ray Chandler, <a href="/A139837/b139837.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 {15, 23, 31, 47, 71} (mod 88).

%t QuadPrimes2[4, -4, 23, 10000] (* see A106856 *)

%o (Magma) [ p: p in PrimesUpTo(3000) | p mod 88 in {15, 23, 31, 47, 71}]; // _Vincenzo Librandi_, Jul 29 2012

%K nonn,easy

%O 1,1

%A _T. D. Noe_, May 02 2008