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Primes p such that Legendre(-5,p) = -1.
3

%I #13 Jan 02 2018 16:06:03

%S 2,11,13,17,19,31,37,53,59,71,73,79,97,113,131,137,139,151,157,173,

%T 179,191,193,197,199,211,233,239,251,257,271,277,293,311,313,317,331,

%U 337,353,359,373,379,397,419,431,433,439,457,479,491,499,557,571,577,593,599,613

%N Primes p such that Legendre(-5,p) = -1.

%C Primes == 2, 11, 13, 17, or 19 (mod 20). - _Robert Israel_, Dec 27 2017

%H Robert Israel, <a href="/A296923/b296923.txt">Table of n, a(n) for n = 1..10000</a>

%p Load the Maple program HH given in A296920. Then run HH(-5,200);

%p select(isprime, {seq(seq(20*i+j,j=[2,11,13,17,19]),i=0..100)}); # _Robert Israel_, Dec 27 2017

%o (PARI) lista(nn) = forprime(p=2, nn, if (kronecker(-5,p) == -1, print1(p, ", "))); \\ _Michel Marcus_, Dec 26 2017

%Y Cf. A296922, A003626.

%K nonn

%O 1,1

%A _N. J. A. Sloane_, Dec 25 2017