A040122 - OEIS

%I #8 Sep 08 2022 08:44:53

%S 2,5,7,11,19,43,79,83,89,107,127,131,139,151,157,167,211,227,239,257,

%T 263,271,283,307,313,317,347,353,359,389,397,421,431,439,449,479,491,

%U 503,523,547,563,571,607,641,659

%N Primes p such that x^4 = 11 has a solution mod p.

%H Vincenzo Librandi, <a href="/A040122/b040122.txt">Table of n, a(n) for n = 1..1000</a>

%t ok [p_]:=Reduce[Mod[x^4 - 11, p]== 0, x, Integers]=!= False; Select[Prime[Range[180]], ok] (* _Vincenzo Librandi_, Sep 12 2012 *)

%o (Magma) [p: p in PrimesUpTo(800) | exists(t){x : x in ResidueClassRing(p) | x^4 eq 11}]; // _Vincenzo Librandi_, Sep 12 2012

%K nonn,easy

%O 1,1

%A _N. J. A. Sloane_.