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%I #15 Jan 17 2018 03:36:16
%S 2,7,11,13,23,29,37,41,43,47,53,83,89,97,109,113,131,139,163,173,181,
%T 191,193,199,239,241,251,257,263,269,271,281,283,293,311,317,337,347,
%U 359,367,373,401,409,419,421,433
%N Primes p such that 19 is not a square mod p.
%C Also, only entries p=1 (mod 4) of the sequence are not squares mod 19 (from the quadratic reciprocity law). - _Lekraj Beedassy_, Jul 21 2004
%H Vincenzo Librandi, <a href="/A038892/b038892.txt">Table of n, a(n) for n = 1..1000</a>
%t Select[Prime@Range[120], JacobiSymbol[19, #] == -1 &] (* _Vincenzo Librandi_, Sep 08 2012 *)
%Y Cf. A297176
%K nonn
%O 1,1
%A _N. J. A. Sloane_.
%E Offset changed from 0 to 1 by _Vincenzo Librandi_, Sep 08 2012