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Primes p such that x^24 = 2 has a solution mod p.
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%I #15 Sep 08 2022 08:44:58

%S 2,23,31,47,71,89,127,167,191,223,233,239,257,263,311,359,383,431,439,

%T 479,503,599,601,647,719,727,743,839,863,881,887,911,919,983,1031,

%U 1103,1151,1217,1223,1289,1319,1327,1367,1399,1423,1433,1439,1471,1487,1511

%N Primes p such that x^24 = 2 has a solution mod p.

%C Complement of A059362 relative to A000040. - _Vincenzo Librandi_, Sep 14 2012

%H R. J. Mathar, <a href="/A049556/b049556.txt">Table of n, a(n) for n = 1..1000</a>

%H <a href="/index/Pri#smp">Index entries for related sequences</a>

%t ok[p_]:= Reduce[Mod[x^24 - 2, p] == 0, x, Integers] =!= False; Select[Prime[Range[300]], ok] (* _Vincenzo Librandi_, Sep 14 2012 *)

%o (Magma) [p: p in PrimesUpTo(1600) | exists(t){x : x in ResidueClassRing(p) | x^24 eq 2}]; // _Vincenzo Librandi_, Sep 14 2012

%Y Cf. A000040, A059362.

%K nonn,easy

%O 1,1

%A _N. J. A. Sloane_