|
%I #23 Sep 08 2022 08:45:18
%S 2,17,23,47,113,137,167,233,257,263,353,383,503,593,617,647,743,857,
%T 863,887,953,977,983,1097,1103,1193,1217,1223,1367,1433,1487,1553,
%U 1583,1607,1697,1823,1847,1913,2063,2087,2153,2207,2273,2297,2393
%N Primes of the form 2x^2 + 15y^2.
%C Discriminant = -120. See A107132 for more information.
%H Vincenzo Librandi and Ray Chandler, <a href="/A107137/b107137.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 {2, 17, 23, 47, 113} (mod 120). - _T. D. Noe_, May 02 2008
%t QuadPrimes2[2, 0, 15, 10000] (* see A106856 *)
%o (Magma) [ p: p in PrimesUpTo(3000) | p mod 120 in {2, 17, 23, 47, 113} ]; // _Vincenzo Librandi_, Jul 24 2012
%o (PARI) list(lim)=my(v=List([2]), s=[17, 23, 47, 113]); forprime(p=11, lim, if(setsearch(s, p%120), listput(v, p))); Vec(v) \\ _Charles R Greathouse IV_, Feb 09 2017
%Y Cf. A139827.
%K nonn,easy
%O 1,1
%A _T. D. Noe_, May 13 2005
|
