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A216884 Primes p such that x^61 = 2 has a solution mod p. 2
2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97, 101, 103, 107, 109, 113, 127, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199, 211, 223, 227, 229, 233, 239, 241, 251, 257, 263, 269, 271 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Complement of A059230 relative to A000040.

Naturally this sequence is not the same as A000040. First disagreement at index 73: a(73)=373, A000040(73)=367. [Bruno Berselli, Sep 20 2012]

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

MATHEMATICA

ok[p_] := Reduce[Mod[x^61 - 2, p] == 0, x, Integers] == True; Select[Prime[Range[150]], ok]

PROG

(MAGMA) [p: p in PrimesUpTo(500) | exists(t){x: x in ResidueClassRing(p) | x^61 eq 2}];

CROSSREFS

Sequence in context: * A216885 A216886 A273960 A100726 A015919 A064555

Adjacent sequences:  A216881 A216882 A216883 * A216885 A216886 A216887

KEYWORD

nonn,easy

AUTHOR

Vincenzo Librandi, Sep 19 2012

STATUS

approved

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Last modified December 13 09:05 EST 2017. Contains 295957 sequences.