# 641491

This number is a prime.

The prime *p* = 641491 is the smallest known counterexample to Masley's suggestion of how one might prove Vandiver's conjecture, i.e., show that the class number *h*(Q(ζ_{p} + ζ_{p}^{-1})) is smaller than *p*. [Poo Sung]

Printed from the PrimePages <primes.utm.edu> © G. L. Honaker and Chris K. Caldwell