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Primes p for which there is no prime q == 2 (mod 3) that is smaller than p and is a quadratic residue modulo p.
1

%I #5 Mar 30 2012 19:00:09

%S 2,3,5,13

%N Primes p for which there is no prime q == 2 (mod 3) that is smaller than p and is a quadratic residue modulo p.

%C Gica proved that if p is a prime different from 2, 3, 5, 13, then a prime q < p exists which is a quadratic residue modulo p and q == 2 (mod 3). His paper has not yet been published, but see A192578 for a reference, link, and examples of a similar result.

%Y Cf. A192578, A192579, A193063.

%K nonn,fini,full

%O 1,1

%A _Jonathan Sondow_, Jul 15 2011