English

Cohen-Macaulay type of orders, generators and ideal classes

Commutative Algebra 2025-02-28 v2 Number Theory

Abstract

In this paper we study the (Cohen-Macaulay) type of orders over Dedekind domains in \'etale algebras. We provide a bound for the type, and give formulas to compute it. We relate the type of the overorders of a given order to the size of minimal generating sets of its fractional ideals, generalizing known results for Gorenstein and Bass orders. Finally, we give a classification of the ideal classes with multiplicator ring of type 22, with applications to the computations of the conjugacy classes of integral matrices and the isomorphism classes of abelian varieties over finite fields.

Keywords

Cite

@article{arxiv.2206.03758,
  title  = {Cohen-Macaulay type of orders, generators and ideal classes},
  author = {Stefano Marseglia},
  journal= {arXiv preprint arXiv:2206.03758},
  year   = {2025}
}

Comments

accepted version

R2 v1 2026-06-24T11:43:13.372Z