Jie Ma

collaborators

8 papers

math.CO2026

Longest cycles intersect linearly in highly connected graphs

Jie Ma, Bo Ning, Ziyuan Zhao

A longstanding conjecture attributed to Smith (1984) asserts that for every $k \geq 2$ , any two longest cycles in a $k$ -connected graph share at least $k$ vertices. In this paper, we…

math.CO2026

An Erdős problem on random subset sums in finite abelian groups

Jie Ma, Quanyu Tang

Let $f (N)$ denote the least integer $k$ such that, if $G$ is an abelian group of order $N$ and $A \subseteq G$ is a uniformly random $k$ -element subset, then with probability at le…

math.CO2026

Dean's conjecture and cycles modulo k

Yufan Luo, Jie Ma, Ziyuan Zhao

Dean conjectured three decades ago that every graph with minimum degree at least $k \geq 3$ contains a cycle whose length is divisible by $k$ . While the conjecture has been verified…

math.CO2025

Spectral supersaturation for color-critical graphs

Longfei Fang, Yongtao Li, Huiqiu Lin +1

A graph is color-critical if it contains an edge whose deletion reduces its chromatic number. This class of graphs, including cliques and odd cycles, plays a central role in extrem…

math.CO2025

Proof of a conjecture of Voss on bridges of longest cycles

Jie Ma, Rongxing Xu

Bridges are a classical concept in structural graph theory and play a fundamental role in the study of cycles. A conjecture of Voss from 1991 asserts that if disjoint bridges $B_1,…

math.CO2025

Intersections of longest cycles in vertex-transitive and highly connected graphs

Jie Ma, Ziyuan Zhao

Motivated by the classical conjectures of Lovász, Thomassen, and Smith, recent work has renewed interest in the study of longest cycles in important graph families, such as vertex-…

math.CO2025

Bisections of graphs under degree constraints

Jie Ma, Hehui Wu

In this paper, we investigate the problem of finding {\it bisections} (i.e., balanced bipartitions) in graphs. We prove the following two results for {\it all} graphs $G$ : (1). $G$ …

math.CO2025

Leaf-to-leaf paths and cycles in degree-critical graphs

Francesco Di Braccio, Kyriakos Katsamaktsis, Jie Ma +2

An $n$ -vertex graph is degree 3-critical if it has $2 n - 2$ edges and no proper induced subgraph with minimum degree at least 3. In 1988, Erdős, Faudree, Gyárfás, and Schelp asked…