A255209 - OEIS

A255209

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

5107, 20771, 51427, 52517, 61417, 66161, 116731, 119359, 128657, 140741, 147647, 150559, 199783, 203773, 213949, 229939, 237283, 261761, 286751, 288929, 303089, 339139, 342373, 381853, 384611, 385657, 475897

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

COMMENTS

p = prime(n) such that A242830(n) = 6.

LINKS

Table of n, a(n) for n=1..27.

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

PROG

(PARI) forprime(p=1, , b=2; i=0; while(b < p, if(Mod(b, p^2)^(p-1)==1, i++); b++); if(i==6, print1(p, ", ")))

CROSSREFS

Cf. A255203, A255204, A255205, A255206, A255207, A255208, A255210.

Sequence in context: A025401 A343987 A343986 * A261462 A215839 A258729

Adjacent sequences: A255206 A255207 A255208 * A255210 A255211 A255212

KEYWORD

nonn,more

AUTHOR

Felix Fröhlich, Feb 17 2015

STATUS

approved