%I #12 Sep 08 2022 08:44:53

%S 2,3,5,29,31,43,47,59,79,89,97,103,107,109,127,149,151,157,181,193,

%T 197,199,211,223,229,233,239,251,257,263,269,277,281,311,313,337,347,

%U 353,359,367,373,383,397,419,431

%N Primes p such that 77 is not a square mod p.

%H Vincenzo Librandi, <a href="/A038962/b038962.txt">Table of n, a(n) for n = 1..1000</a>

%t Select[Prime@Range[120], JacobiSymbol[77, #] == - 1 &] (* _Vincenzo Librandi_, Sep 09 2012 *)

%o (Magma) [2] cat [ p: p in PrimesUpTo(431) | not IsSquare(R! 77) where R:= ResidueClassRing(p) ]; // _Vincenzo Librandi_, Sep 10 2012

%K nonn,easy

%O 1,1

%A _N. J. A. Sloane_.

%E Offset changed from 0 to 1 by _Vincenzo Librandi_, Sep 09 2012