|
|
A059310
|
|
Primes p such that x^21 = 2 has no solution mod p.
|
|
2
|
|
|
7, 13, 19, 29, 37, 43, 61, 67, 71, 73, 79, 97, 103, 113, 127, 139, 151, 163, 181, 193, 197, 199, 211, 239, 241, 271, 281, 313, 331, 337, 349, 367, 373, 379, 409, 421, 449, 463, 487, 491, 523, 541, 547, 571, 577, 607, 613, 617, 619, 631, 659, 661, 673, 701
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,1
|
|
COMMENTS
|
|
|
LINKS
|
|
|
MATHEMATICA
|
ok[p_] := Reduce[Mod[x^21 - 2, p] == 0, x, Integers] == False; Select[Prime[Range[150]], ok] (* Vincenzo Librandi, Sep 20 2012 *)
|
|
PROG
|
(Magma) [p: p in PrimesUpTo(710) | not exists{x: x in ResidueClassRing(p) | x^21 eq 2}]; // Vincenzo Librandi, Sep 20 2012
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn,easy
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|