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%I #20 Nov 04 2018 01:38:48
%S 3,5,7,23,29,41,43,47,61,67,83,89,101,103,107,109,127,149,163,167,181,
%T 223,227,229,241,263,269,281,283,307,347,349,367,383,389,401,409,421,
%U 443,449,461,463,467,487,503,509,521,523,541,547,563,569,587,601,607,641,643
%N Primes p such that Legendre(-5,p) = 0 or 1.
%C Primes == 1, 3, 5, 7, or 9 (mod 20). Primes whose 10's digit is even. - _Robert Israel_, Dec 27 2017
%H Robert Israel, <a href="/A296922/b296922.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = A240920(n+1) for n >= 1. - _Georg Fischer_, Oct 30 2018
%p Load the Maple program HH given in A296920. Then run HH(-5,200);
%p select(isprime, {seq(seq(20*i+j,j=[1,3,5,7,9]),i=0..100)}); # _Robert Israel_, Dec 27 2017
%t Select[Prime@ Range@ 120, MemberQ[{0, 1}, KroneckerSymbol[-5, #]] &] (* or *)
%t Select[Prime@ Range@ 120, MemberQ[Range[1, 9, 2], Mod[#, 20]] &] (* _Michael De Vlieger_, Jan 02 2018 *)
%o (PARI) lista(nn) = forprime(p=2, nn, if (kronecker(-5,p) >= 0, print1(p, ", "))); \\ _Michel Marcus_, Dec 26 2017
%Y Cf. A139513, A240920, A296920, A296923.
%K nonn
%O 1,1
%A _N. J. A. Sloane_, Dec 25 2017
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