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20202026
most citedThe Lemmens-Seidel conjecture and forbidden subgraphs

2 citations · 3 across the 20 of their papers we have counts for

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19 papers · 1 filter

math.CO2026

A Near-Optimal Linear Range for the Erdős Matching Conjecture

Mengyu Cao, Hong Liu, Haixiang Zhang

The Erdős Matching Conjecture is governed by two competing ways of excluding disjoint edges: one may concentrate all edges on fewer than vertices, or force every edg…

math.CO2026

A Sharp Spectral Erdős--Ko--Rado Theorem for Uniform Hypergraphs

Mengyu Cao, Mei Lu, Haixiang Zhang

The spectral Erdős--Ko--Rado problem asks for the largest adjacency-tensor spectral radius of a -intersecting -uniform family. Keevash, Lenz and Mubayi proved that, for fixed…

math.CO2026

On Erdős--Ko--Rado and Hilton--Milner Theorems for Direct Products

Tian Yao, Mengyu Cao, Kaishun Wang

We investigate -intersecting families in direct-product set systems obtained by prescribing the number of selected elements in each part of a partitioned ground set. For a finit…

math.CO2026

Entropy Transference for Rainbow--Free Colourings of Random Graphs

Mengyu Cao, Mei Lu, Haixiang Zhang

Let be a fixed graph with that contains two adjacent edges, and let be fixed. We establish an entropy-transference principle for rainbow--free edge…

math.CO2026

Erdős--Ko--Rado and Hilton--Milner Theorems in the Partition Lattice

Mengyu Cao, Jiaqi Liao, Haixiang Zhang

Let be the graphic matroid of the complete graph, and let be its rank- flats. We study families sa…

math.CO2026

Degree Power Sums in Extremal Set Systems

Mengyu Cao, Mei Lu, Haixiang Zhang

For a family and , let and $\ell_{r,p}(\mathcal F)=\sum_{R\in\binom{[n]}r}…

math.CO2026

Projective Ore-Degree Conditions for Intersection Theorems in Vector Spaces

Mengyu Cao, Mei Lu, Xuyang Yan +1

Let be an -dimensional vector space over the finite field , and let . The \emph{projective Ore-degree} of $\mat…

math.CO2026

Matchings and Near-Optimal 2-Factor Packings in Percolated Vertex-Transitive Graphs

Mengyu Cao, Mei Lu, Xiamiao Zhao

Let be a connected simple vertex-transitive graph on vertices with degree , and let be the random spanning subgraph obtained by retaining each edge of independ…

math.CO2026

On degree bounds of -uniform hypergraphs with bounded matching number

Haixiang Zhang, Mengyu Cao, Mei Lu

We study the connection between the degree sequence of a -uniform hypergraph and the size of its largest matching. Let be a -uniform hypergraph on vertices…

math.CO2026

Counting sunflowers with restricted matching number

Haixiang Zhang, Mengyu Cao, Mei Lu

For , let denote its matching number and let denote the codegree of a -set . We study the codegree mo…

math.CO2025

Edge pancyclic Cayley graphs on symmetric group

Mengyu Cao, Mei Lu, Zequn Lv +1

We study the derangement graph whose vertex set consists of all permutations of , where two vertices are adjacent if and only if their corresponding permutati…

math.CO2025

Generalizations of the Erdős Matching Conjecture for the -Matching Number

Mengyu Cao, Mei Lu, Haixiang Zhang

We write finite set systems as uniform hypergraphs. A \emph{-matching} in a -uniform hypergraph is a set of hyperedges any two of which intersect in fewer than vertices.…

math.CO2025

Simplices in -intersecting families for vector spaces

Haixiang zhang, Mengyu Cao, Mei Lu +1

Let be an -dimensional vector space over the finite field and denote the family of all -dimensional subspaces of . A family $\mathcal{F}\s…

math.CO2024

Treewidth of generalized Hamming graph, bipartite Kneser graph and generalized Petersen graph

Yichen Wang, Mengyu Cao, Zequn Lv +1

Let and be positive integers. Write . The generalized Hamming graph is the graph whose vertex set is the cartesian product of copie…

math.CO2023

Hilton-Milner theorem for -multisets

Jiaqi Liao, Zequn Lv, Mengyu Cao +1

Let and . A -multiset in is a -set whose elements are integers from , an…

math.CO2023

Erdős-Ko-Rado Theorem for Bounded Multisets

Jiaqi Liao, Zequn Lv, Mengyu Cao +1

Let be positive integers with . A -multiset of is a collection of integers from the set in which the integers c…

math.CO2022★ 1 cited

Edge pancyclic derangement graphs

Zequn Lv, Mengyu Cao, Mei Lu

We consider the derangement graph in which the vertices are permutations of . Two vertices are joined by an edge if the corresponding permutations differ in every…

math.CO2022

Some intersection theorems for finite sets

Mengyu Cao, Mei Lu, Benjian Lv +1

Let , , and be positive integers with , and a family of -subsets of an -set . The families $\mathcal…

math.CO2020★ 2 cited

The Lemmens-Seidel conjecture and forbidden subgraphs

Meng-Yue Cao, Jack H, Koolen +2

In this paper we show that the conjecture of Lemmens and Seidel of 1973 for systems of equiangular lines with common angle is true. Our main tool is forbidden subgr…