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Primes p such that 6 is a square mod p.
7

%I #10 Jul 13 2012 09:38:33

%S 2,3,5,19,23,29,43,47,53,67,71,73,97,101,139,149,163,167,173,191,193,

%T 197,211,239,241,263,269,283,293,307,311,313,317,331,337,359,379,383,

%U 389,409,431,433,457,461,479,499,503,509,523,547,557,571,577,599,601,619,643,647

%N Primes p such that 6 is a square mod p.

%C Also: for p>6, primes of the form 24*k +/-1 or +-5. - _Zak Seidov_ Feb 01 2008.

%H Vincenzo Librandi, <a href="/A038876/b038876.txt">Table of n, a(n) for n = 1..1000</a>

%p with(numtheory); t1:=[]; for n from 1 to 500 do p:=ithprime(n); if quadres(6,p) = 1 then t1:=[op(t1),p]; fi; od: t1;

%t Select[Prime[Range[3000]],JacobiSymbol[6,#]!=-1&] (* _Vincenzo Librandi_, Jul 13 2012 *)

%K nonn

%O 1,1

%A _N. J. A. Sloane_.