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A059858 Primes p such that x^5 == 2 (mod p) has five solutions. 0
151, 241, 251, 431, 571, 641, 911, 971, 1181, 1811, 2011, 2351, 2381, 2411, 2731, 3061, 3121, 3221, 3251, 3301, 3331, 3361, 3391, 3541, 3761, 3821, 3881, 4211, 4751, 4861, 4871, 4931, 5021, 5381, 5441, 5471, 5581, 5641, 5711, 5821, 5861 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

For any prime modulus, there must be exactly 0, 1 or 5 solutions to the equation with x between 0 and p - 1.

Primes == 1 (mod 5) such that 2 is a quintic residue, that is, primes p such that 2^((p-1)/5) == 1 (mod p). - Jianing Song, Jan 27 2019

LINKS

Table of n, a(n) for n=1..41.

PROG

(PARI) forstep(p=11, 5000, 10, if(isprime(p)&&Mod(2, p)^((p-1)/5)==1, print1(p, ", "))) \\ Jianing Song, Jan 27 2019

CROSSREFS

Cf. A040159.

Sequence in context: A142225 A334769 A334931 * A152310 A276264 A070182

Adjacent sequences:  A059855 A059856 A059857 * A059859 A059860 A059861

KEYWORD

nonn

AUTHOR

Don Reble, Sep 20 2001

STATUS

approved

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Last modified July 5 23:36 EDT 2020. Contains 335475 sequences. (Running on oeis4.)