A038888 - OEIS

%I #10 Oct 01 2013 17:57:28

%S 13,19,23,29,31,37,41,47,73,79,83,89,97,101,107,139,149,151,157,167,

%T 193,199,211,227,263,269,271,277,281,313,331,337,347,373,379,383,389,

%U 397,401,433,439,443,449,457,461

%N Primes p such that 15 is not a square mod p.

%C Subset of A040136.

%C Also primes p such that p divides 5^(p-1)/2 + 3^(p-1)/2. - _Cino Hilliard_, Sep 06 2004

%H Vincenzo Librandi, <a href="/A038888/b038888.txt">Table of n, a(n) for n = 1..1000</a>

%t Select[Prime@Range[120], JacobiSymbol[15, #] == -1 &] (* _Vincenzo Librandi_, Sep 08 2012 *)

%K nonn

%O 1,1

%A _N. J. A. Sloane_.