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A326615 a(n) is the smallest prime p such that Sum_{primes q <= p} Kronecker(n,q) > 0, or 0 if no such prime exists.

%I A326615 #20 Jul 26 2019 18:27:37
%S A326615 2,11100143,61981,3,2082927221,5,2,11100143,2,3,577,61463,2083,11,2,3,
%T A326615 2,11100121,5,2082927199,1217,3,2,5,2,17,61981,3,719,7,2,11100143,2,3,
%U A326615 23,5,11,31,2,3,2,13,17,7,2082927199,3,2,61463,2,11100121,7,3,17,5,2,11,2,3,31,7,5,41,2,3
%N A326615 a(n) is the smallest prime p such that Sum_{primes q <= p} Kronecker(n,q) > 0, or 0 if no such prime exists.
%H A326615 Richard N. Smith, <a href="/A326615/b326615.txt">Table of n, a(n) for n = 1..4096</a>
%F A326615 a(A003658(n)) = A306499(n).
%F A326615 a(n) = 2 iff n == 1 or 7 mod 8 (see A047522).
%F A326615 a(n) = 3 iff n == 4 mod 6 (see A016957).
%o A326615 (PARI) a(n) = my(i=0); forprime(p=2, oo, i+=kronecker(n, p); if(i>0, return(p))) \\ after _Jianing Song_ in A306499
%Y A326615 Cf. A306499, A306500.
%K A326615 nonn
%O A326615 1,1
%A A326615 _Richard N. Smith_, Jul 15 2019