A255210 Primes p for which exactly seven bases b with 1 < b < p exist such that p is a base-b Wieferich prime.

103291, 491531, 534851, 804367, 997961, 1026899, 1062427, 1457389, 1550513, 2327629, 2602307, 3093121, 3137257, 3181481, 3412741, 3497381, 3720179, 3814253, 4087301, 4234057, 4891973, 5063087, 5131237, 5194789, 5736611, 6253349, 6903191, 6906469, 6945047

Offset: 1

Author

Felix Fröhlich, Mar 07 2015

Keywords

• nonn

Comments

p = prime(n) such that A242830(n) = 7.

Links

• R. Fischer, Thema: Fermatquotient B^(P-1) == 1 (mod P^2) Fermatquotienten mit extremen Erst-Basen

Crossrefs

Cf. A255203, A255204, A255205, A255206, A255207, A255208, A255209.

Programs

PARI

forprime(p=1, , b=2; i=0; while(b < p, if(Mod(b, p^2)^(p-1)==1, i++); b++); if(i==7, print1(p, ", ")))