The Erdős--Ginzburg--Ziv theorem for finite groups
Abstract
Let G be a finite group, and let p be the smallest prime divisor of |G|. The Gao constant E(G) is the least integer ℓ such that every sequence over G of length ℓ contains a subsequence of length |G| whose terms can be ordered to have product equal to the identity. In 1961, Erdős, Ginzburg and Ziv proved that every sequence of 2n−1 integers has an n-term subsequence whose sum is divisible by n; equivalently, E(Cn)≤ 2n−1, where Cn denotes the cyclic group of order n. In this paper, we prove that E(G)≤ |G|+|G|/p−1 whenever G contains no cyclic subgroup of index p. Consequently, every finite non-cyclic group satisfies E(G)≤ |G|+|G|/p+p−2, with equality if and only if G contains a cyclic subgroup of index p. This establishes the conjectured upper bound for the Gao constant and provides a complete characterization of the equality case.
Related
- Generalized Erdős--Ginzburg--Ziv Constants for finite abelian groups of rank three
- On the Erdős--Ginzburg--Ziv Problem for ℤnr
- Inverse Zero-Sum Problems of Erdős--Ginzburg--Ziv constant: Property C and Property D conjectures
- The Erdős--Ginzburg--Ziv constant of Cnr for even n: rigid sequences, products, and growth beyond Harborth's bound
- Extensions of Hindman's theorem via finite colorings of topological groups
BibTeX
@misc{qu2026erdősginzburgziv,
title = {{The Erdős--Ginzburg--Ziv theorem for finite groups}},
author = {Yongke Qu},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.26122},
eprint = {2610.26122},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.26122},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - The Erdős--Ginzburg--Ziv theorem for finite groups
AU - Yongke Qu
PY - 2026
DA - 2026/10/19
PB - arXiv
DO - 10.48550/arxiv.2610.26122
UR - https://arxiv.org/abs/2610.26122
AB - Let G be a finite group, and let p be the smallest prime divisor of |G|. The Gao constant E(G) is the least integer ℓ such that every sequence over G of length ℓ contains a subsequence of length |G| whose terms can be ordered to have product equal to the identity. In 1961, Erdős, Ginzburg and Ziv proved that every sequence of 2n−1 integers has an n-term subsequence whose sum is divisible by n; equivalently, E(C_n)≤ 2n−1, where C_n denotes the cyclic group of order n. In this paper, we prove that E(G)≤ |G|+|G|/p−1 whenever G contains no cyclic subgroup of index p. Consequently, every finite non-cyclic group satisfies E(G)≤ |G|+|G|/p+p−2, with equality if and only if G contains a cyclic subgroup of index p. This establishes the conjectured upper bound for the Gao constant and provides a complete characterization of the equality case.
ER -