English

Higher-order Carmichael numbers

Number Theory 2007-05-23 v1 Commutative Algebra

Abstract

We define a Carmichael number of order m to be a composite integer n such that nth-power raising defines an endomorphism of every Z/nZ-algebra that can be generated as a Z/nZ-module by m elements. We give a simple criterion to determine whether a number is a Carmichael number of order m, and we give a heuristic argument (based on an argument of Erdos for the usual Carmichael numbers) that indicates that for every m there should be infinitely many Carmichael numbers of order m. The argument suggests a method for finding examples of higher-order Carmichael numbers; we use the method to provide examples of Carmichael numbers of order 2.

Keywords

Cite

@article{arxiv.math/9812089,
  title  = {Higher-order Carmichael numbers},
  author = {Everett W. Howe},
  journal= {arXiv preprint arXiv:math/9812089},
  year   = {2007}
}

Comments

9 pages, AMS-LaTeX