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%I #31 Feb 17 2022 11:38:07
%S 2,13,17,19,43,47,53,59,67,83,89,101,103,127,137,149,151,157,179,191,
%T 223,229,239,251,257,263,271,281,293,307,331,349,353,359,373,383,389,
%U 409,421,433,443,457,461,463,467,491,509,523,557,563,569,577,587,593
%N Primes p such that 17 is a square mod p.
%C Also primes of the form 2*x^2+x*y-2*y^2 (as well as of the form 2*x^2+5*x*y+y^2). Discriminant = 17. Class = 1. This was originally a separate entry, submitted by Laura Caballero Fernandez, Lourdes Calvo Moguer, Maria Josefa Cano Marquez, Oscar Jesus Falcon Ganfornina and Sergio Garrido Morales (oscfalgan(AT)yahoo.es), Jun 06 2008. _R. J. Mathar_ proved that this coincides with the present sequence, Jul 22 2008
%C Also, primes which are a square (mod 17) (or, (mod 34), cf. A191025). - _M. F. Hasler_, Jan 15 2016
%D Z. I. Borevich and I. R. Shafarevich, Number Theory.
%H Vincenzo Librandi, <a href="/A038889/b038889.txt">Table of n, a(n) for n = 1..1000</a>
%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)
%H D. B. Zagier, <a href="https://doi.org/10.1007/978-3-642-61829-1">Zetafunktionen und quadratische Körper</a>, Springer, 1981.
%t Select[Prime[Range[200]],JacobiSymbol[17,#]!=-1&] (* _Harvey P. Dale_, Sep 20 2011 *)
%o (PARI) is(n)=isprime(n)&&issquare(Mod(17,n)) \\ _Charles R Greathouse IV_, Mar 21 2013
%Y Cf. A038889 (17 is a square mod p); A141111, A141112 (d=65).
%Y Primes in A035258.
%K nonn
%O 1,1
%A _N. J. A. Sloane_.
%E Edited by _N. J. A. Sloane_, Jul 28 2008 at the suggestion of _R. J. Mathar_
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