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%I M3806 #17 Dec 31 2017 16:40:25
%S 5,11,13,17,23,41,43,61,67,71,73,79,89,97,101,107,127,151,157,163,173,
%T 179,181,191,211,229,239,241,257,263,269,293,313,331,347,349,353,359,
%U 379,397,409,431,433,443,461,463,487,491,499,509,521,547,571,577,593,599
%N Inert rational primes in Q(sqrt 7), or, 7 is not a square mod p.
%C Primes congruent to 5, 11, 13, 15, 17, 23 (modulo 28). - _Michael Somos_, Aug 14 2012
%D H. Hasse, Number Theory, Springer-Verlag, NY, 1980, p. 498.
%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%H Vincenzo Librandi, <a href="/A003632/b003632.txt">Table of n, a(n) for n = 1..5000</a>
%H <a href="https://oeis.org/wiki/Index_to_OEIS:_Section_Pri#primes_decomp_of">Index to sequences related to decomposition of primes in quadratic fields</a>
%t Select[Prime[Range[1000]],MemberQ[{5,11,13,15,17,23},Mod[#,28]]&] (* _Vincenzo Librandi_, Aug 20 2012 *)
%o (PARI) {a(n) = local( cnt, m ); if( n<1, return( 0 )); while( cnt < n, if( isprime( m++) && kronecker( 7, m )== -1, cnt++ )); m} /* _Michael Somos_, Aug 14 2012 */
%K nonn
%O 1,1
%A _N. J. A. Sloane_, _Mira Bernstein_
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