Li-Hua Feng

activity

20242026

most citedSpectral supersaturation: Triangles and bowties

5 citations · 11 across the 17 of their papers we have counts for

collaborators

17 papers

math.CO2026

Spectral extremal hypergraphs without long Berge cycles

Lihua Feng, Lu Lu, Tingzeng Wu

Let $r \geq 3$ and $k \geq 2 r + 1$ be fixed integers. We determine, for all sufficiently large $n$ , the maximum adjacency-tensor spectral radius of an $n$ -vertex $r$ -uniform hypergraph c…

math.CO2026

Rigidity and stability for biased cross-intersecting families

Yongjiang Wu, Lihua Feng

Let $p = (p_{1}, \dots, p_{n})$ and $q = (q_{1}, \dots, q_{n})$ belong to $(0, 1/2]^{n}$ , and let $μ_{p}$ and $μ_{q}$ be the associated measures on $2^{[n]}$ . Suppos…

math.CO2026

The binomial norm of intersecting-union families

Yongjiang Wu, Lihua Feng

In a 2021 survey on Katona's circle method, Frankl conjectured that every family $F \subseteq 2^{[n]}$ in which any two members intersect and no two members cover $[n]$ sa…

math.CO2026

Random partition for Tokushige's $r$ -wise intersecting conjecture

Yongjiang Wu, Lihua Feng

Let $r \geq 3$ and let $1 > p_{1} \geq p_{2} \geq \dots \geq p_{n} > 0$ . Let $μ_{p}$ denote the product measure on $2^{[n]}$ where each coordinate $i$ is included independently with probabil…

math.CO2026

Bollobás-type inequalities for subspaces via weight invariance

Zhiyi Liu, Lihua Feng, Tingzeng Wu

Let $V$ be an $n$ -dimension real vector space with a direct sum decomposition $V = V_{1} \oplus \dots \oplus V_{r}$ . Let $P = {(A_{i}, B_{i}) : i \in [m]}$ be a skew Bollobás…

math.CO2026

Subspace variations of the weighted skew Bollobás theorem

Yongjiang Wu, Yongtao Li, Lu Lu +1

Let $V$ be a finite-dimensional real vector space. A collection $P = {(A_{i}, B_{i})}_{i = 1}^{m}$ of pairs of subspaces of $V$ is called a skew Bollobás system if $\dim(A_i\cap…

math.CO2025

The number of rooted spanning forests of bicirculant graphs

Jing Yang, Lihua Feng, Rongrong Lu +1

A bi-Cayley graph over the cyclic group $(Z_{n}, +)$ is called a bicirculant graph. Let $Γ = B C (Z_{n}; R, T, S)$ be a bicirculant graph with $R=-R\subseteq \mathbb{Z}_n\s…

math.CO2025

The product measures of cross $t$ -intersecting families

Yongjiang Wu, Yongtao Li, Zhiyi Liu +1

We investigate the product measures of intersection problems in extremal combinatorics. Invoking a recent result of He--Li--Wu--Zhang, we prove that for any $n \geq t \geq 3$ and…

math.CO2025

Non-uniform pairwise cross $t$ -intersecting families

Yongjiang Wu, Yongtao Li, Tingzeng Wu +1

Let $n \geq t \geq 1$ and $A_{1}, A_{2}, \dots, A_{m} \subseteq 2^{[n]}$ be non-empty families. We say that they are pairwise cross $t$ -intersecting if $|A…

math.CO2025

Two results on set families: sturdiness and intersection

Yongjiang Wu, Zhiyi Liu, Lihua Feng +1

This paper resolves two open problems in extremal set theory. For a family $F \subseteq 2^{[n]}$ and $i, j \in [n]$ , we denote $\mathcal{F} (i,\bar{j})=\{F\backslash\{i\}:…

math.CO2025

Spectral extremal problems for non-bipartite graphs without odd cycles

Lantao Zou, Lihua Feng, Yongtao Li

A well-known result of Mantel asserts that every $n$ -vertex triangle-free graph $G$ has at most $⌊ n^{2} /4 ⌋$ edges. Moreover, Erdős proved that if $G$ is further non-bip…

math.CO2024★ 1 cited

A result for hemi-bundled cross-intersecting families

Yongjiang Wu, Lihua Feng, Yongtao Li

Two families $F$ and $G$ are called cross-intersecting if for every $F \in F$ and $G \in G$ , the intersection $F \cap G$ is non-empty. It is si…

math.CO2024

Stabilities of the Kleitman diameter theorem

Yongjiang Wu, Yongtao Li, Lihua Feng +2

Let $F$ be a family of subsets of $[n]$ . The diameter of $F$ is the maximum size of symmetric differences among pairs of its members. Resolving a conjecture of…

math.CO2024

Maximal intersecting families revisited

Yongjiang Wu, Yongtao Li, Lihua Feng +2

The well-known Erdős--Ko--Rado theorem states that for $n > 2 k$ , every intersecting family of $k$ -sets of $[n] := {1, \dots, n}$ has at most $(k - 1 n - 1)$ sets, and the extre…

math.CO2024

A spectral Lovász-Simonovits theorem

Yongtao Li, Lihua Feng, Yuejian Peng

A fundamental result in extremal graph theory is attributed to Mantel's theorem, which states that every graph on $n$ vertices with more than $⌊ n^{2} /4 ⌋$ edges must con…

math.CO2024★ 5 cited

Spectral supersaturation: Triangles and bowties

Yongtao Li, Lihua Feng, Yuejian Peng

Recently, Ning and Zhai (2023) proved that every $n$ -vertex graph $G$ with $λ (G) \geq ⌊ n^{2} /4 ⌋$ has at least $⌊ n /2 ⌋ - 1$ triangles, unless $G=K_{\lcei…

math.CO2024★ 5 cited

A spectral Erdős-Faudree-Rousseau theorem

Yongtao Li, Lihua Feng, Yuejian Peng

A well-known theorem of Mantel states that every $n$ -vertex graph with more than $⌊ n^{2} /4 ⌋$ edges contains a triangle. An interesting problem in extremal graph theory…

Spectral extremal hypergraphs without long Berge cycles

Rigidity and stability for biased cross-intersecting families

The binomial norm of intersecting-union families

Random partition for Tokushige's r-wise intersecting conjecture

Bollobás-type inequalities for subspaces via weight invariance

Subspace variations of the weighted skew Bollobás theorem

The number of rooted spanning forests of bicirculant graphs

The product measures of cross t-intersecting families

Non-uniform pairwise cross t-intersecting families

Two results on set families: sturdiness and intersection

Spectral extremal problems for non-bipartite graphs without odd cycles

A result for hemi-bundled cross-intersecting families

Stabilities of the Kleitman diameter theorem

Maximal intersecting families revisited

A spectral Lovász-Simonovits theorem

Spectral supersaturation: Triangles and bowties

A spectral Erdős-Faudree-Rousseau theorem

Random partition for Tokushige's $r$ -wise intersecting conjecture

The product measures of cross $t$ -intersecting families

Non-uniform pairwise cross $t$ -intersecting families