The universal zero-sum invariant and weighted zero-sum for infinite abelian groups II
Abstract
Let be an abelian group, and let be the free commutative monoid with basis , and the set consisting of all minimal zero-sum subsequences over . For any subset , we define the universal zero-sum invariant as the minimal positive integer such that every sequence over of length contains a subsequence lying in . The classical Davenport constant for can also be written as . We give a complete classification of all finite abelian groups for which is a minimal set to represent the Davenport constant. We also investigate the weighted Davenport constant over abelian groups (which may be infinite). Let and be abelian groups, and let denote a weight set. We reinterpret the weighted Davenport constant in terms of coverings of Cartesian powers by kernels of induced homomorphisms arising from tuples in ; these homomorphisms are naturally linked to coproducts in the category of abelian groups. This motivates the notion of kernel-cover compactness, a property characterizing when such kernel coverings admit finite subcovers. We establish a correspondence between weighted zero-sum invariants and kernel-cover structures, where the bound is equivalent to a canonical kernel-cover property on . We further study finite reduction phenomena for infinite weight sets and provide sufficient conditions ensuring uniform kernel-cover compactness. The present work constitutes a follow-up to [G. Wang, Comm. Algebra, 2025].
Keywords
Cite
@article{arxiv.2607.02132,
title = {The universal zero-sum invariant and weighted zero-sum for infinite abelian groups II},
author = {Guoqing Wang},
journal= {arXiv preprint arXiv:2607.02132},
year = {2026}
}
Comments
17 pages