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%I #11 Feb 14 2019 16:15:57
%S 3,5,5,3,11,13,3,5,7,3,7,5,3,11,7,3,5,5,3,11,13,3,5,13,3,11,5,3,7,7,3,
%T 5,5,3,19,7,3,5,7,3,13,5,3,7,11,3,5,5,3,7,7,3,5,13,3,11,5,3,11,7,3,5,
%U 5,3,7,19,3,5,11,3,7,5,3,7,11,3,5,5,3,11,7,3,5,13,3,7,5
%N a(n) is the smallest prime p such that -n is not a square mod p.
%C a(n) is the smallest odd prime p such that Kronecker(-n,p) = -1.
%C A companion sequence to A144294.
%C Conjecture: lim sup log(a(n))/log(n) = 0.
%F a(n) = 3 if and only if n == 1 (mod 3).
%F a(n) = 5 if and only if n == 2, 3, 8, 12 (mod 15).
%o (PARI) a(n) = forprime(p=3, , if(kronecker(-n, p)<0, return(p)))
%Y Cf. A144294.
%Y See A306220 for another version.
%K nonn
%O 1,1
%A _Jianing Song_, Jan 30 2019
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