A255206 Primes p for which exactly three bases b with 1 < b < p exist such that p is a base b Wieferich prime.

269, 331, 571, 863, 883, 907, 1097, 1103, 1291, 1579, 1697, 1741, 2179, 2213, 2221, 2281, 2309, 2311, 2551, 2671, 2677, 2693, 2707, 2789, 2791, 3191, 3253, 3571, 3617, 3877, 3931, 4049, 4787, 4813, 4987, 5021, 5153, 5197, 5227, 5347, 5519, 5669, 5689, 5693

Offset

1,1

Comments

p = prime(n) such that A242830(n) = 3.

Links

Table of n, a(n) for n=1..44.

Prog

(PARI) forprime(p=1, , b=2; i=0; while(b < p, if(Mod(b, p^2)^(p-1)==1, i++); b++); if(i==3, print1(p, ", ")))

Crossrefs

Cf. A255203, A255204, A255205, A255207, A255208, A255209, A255210.

Sequence in context: A273552 A341181 A073026 * A142636 A142385 A142823

Adjacent sequences: A255203 A255204 A255205 * A255207 A255208 A255209

Keyword

nonn

Author

Felix Fröhlich, Feb 17 2015

Status

approved