A255838 Smallest base-b Wieferich prime larger than b, where b = prime(n).

1093, 11, 20771, 491531, 71, 863, 46021, 43, 2481757

Offset

1,1

Comments

a(10), if it exists, is larger than approximately 5.9*10^13, corresponding to the first odd Wieferich prime in base 29 (see Fischer link).

Links

Table of n, a(n) for n=1..9.

R. Fischer,  Thema: Fermatquotient B^(P-1) == 1 (mod P^2)

Prog

(PARI) forprime(b=1, 20, forprime(p=b, , if(Mod(b, p^2)^(p-1)==1, print1(p, ", "); break({1}))))

Crossrefs

Cf. A247072.

Sequence in context: A271100 A258368 A174422 * A253234 A138698 A342390

Adjacent sequences: A255835 A255836 A255837 * A255839 A255840 A255841

Keyword

nonn,hard,more

Author

Felix Fröhlich, Mar 07 2015

Status

approved