
Glossary: Prime Pages: Top 5000: 
By Fermat's Little theorem any prime p divides
2^{p1}1. A prime p is
a Wieferich prime if
p^{2} divides 2^{p1}1.
In 1909 Wieferich proved that if the first case
of Fermat's last theorem is false for the exponent p,
then p satisfies this criterion.
Since 1093 and 3511 are the only known
such primes (and they have been checked to
at least 32,000,000,000,000), this is a
strong statement!
In 1910 Mirimanoff proved the analogous theorem for 3 (that the first case of Fermat's last theorem is false for the exponent p, then p^{2} divides 3^{p1}1), but there is little glory in being second. Such numbers are not called Mirimanoff primes. Are there infinitely many Wieferich primes? Probably, but little is known about their distribution. In 1988 J. H. Silverman [Silverman88] proved that the abcconjecture implies that for any positive integer a > 1, there exists infinitely many primes p such that p^{2} does not divide a^{p1}1. But this is a long way from showing there are finitely many Wieferich primes.
See Also: WilsonPrime, FermatQuotient, CatalansProblem Related pages (outside of this work) References:
Chris K. Caldwell © 19992014 (all rights reserved)
