Lihua You

activity

20242026

collaborators

13 papers

math.CO2026

Edge and spectral conditions for rainbow bipancyclicity in bipartite graph collections

Lihua You, Xiaoxue Zhang, Xinghui Zhao

Let $G = {G_{1}, \dots, G_{2 n}}$ be a collection of not necessarily distinct balanced bipartite graphs of order $2 n$ with a common bipartition $V = (X, Y)$ . A cycle $C$ with $V(C…

math.CO2026

Edge and spectral conditions for rainbow pancyclicity in graph collections

Lihua You, Xiaoxue Zhang, Xinghui Zhao

Let $G = {G_{1}, \dots, G_{n}}$ be a collection of not necessarily distinct $n$ -vertex graphs with a common vertex set $V$ . A cycle $C$ with $V (C) \subseteq V$ and $|E(C)|\leq…

math.CO2026

Two problems on booksize and triangular edges in Nosal graphs

Xinghui Zhao, Lihua You, Jing Zeng +1

A graph $G$ with $m$ edges is said to be a Nosal graph if $ρ (G) > m$ . For a graph $G$ , we write $bk (G)$ for its maximum book size and $τ (G)$ for the number of edges contained…

math.CO2026

The maximum number of cycles of a given length in a nonhamiltonian graph

Jifu Lin, Xiaolin Wang, Lihua You

In 2026, Li and Zhan characterized the nonhamiltonian graphs of order $n$ with the maximum number of paths of length $k$ , where $n$ and $k$ are integers satisfying $1\leq k\leq n-1…

math.CO2026

The signless Laplacian spectral radius of graphs without disjoint cliques

Xinghui Zhao, Lihua You, Jing Zeng

A graph $G$ is $(t + 1) K_{r + 1}$ -free if it contains no $t + 1$ pairwise vertex-disjoint copies of $K_{r + 1}$ . Moon [Canad. J. Math. 20 (1968) 95-102] and Simonovits [Theory of Graphs (P…

math.CO2026

The saturation number of $K_{t}^{s}$

Xinghui Zhao, Lihua You, Xiaoxue Zhang

For a given graph $F$ , a graph $G$ is said to be $F$ -saturated if $G$ contains no copy of $F$ but for any edge $uv \in / E (G)$ , $G + uv$ contains a copy of $F$ . The saturation number…

math.CO2025

Saturation numbers of $K_{2} \lor P_{k}$

Xiaoxue Zhang, Lihua You, Xinghui Zhao

A graph $G$ is called $H$ -saturated if $G$ contains no copy of $H$ , but $G + e$ contains a copy of $H$ for any edge $e \in E (G)$ . The saturation number of $H$ is the minimu…

math.CO2025

On the characterizations of $D_{k} \ D_{k - 2}$

Jing Zeng, Lihua You, Xinghui Zhao +1

The determinant of a tournament $T$ , denoted by $det (T)$ , is defined as the determinant of the skew-adjacency matrix of $T$ . It is well-known that $det (T)$ is equal to $0$ if $n$ …

math.CO2025

Oriented diameter of graphs with diameter $4$ and given edge girth

Jifu Lin, Lihua You

Let $f (d)$ be the smallest value for which every bridgeless graph $G$ with diameter $d$ admits a strong orientation $G$ such that the diameter of $\overrightarrow{…

math.CO2025

The connectedness of friends-and-strangers graphs about graph parameters and others

Xinghui Zhao, Lihua You, Jifu Lin +1

Let $X$ and $Y$ be two graphs of order $n$ . The friends-and-strangers graph $FS (X, Y)$ of $X$ and $Y$ is a graph whose vertex set consists of all bijections $σ: V(X)\righta…

math.CO2024

Spectral conditions for spanning $k$ -trees or $k$ -ended-trees of $t$ -connected graphs

Jifu Lin, Zenan Du, Xinghui Zhao +1

Let $G$ be a connected graph of order $n$ . A spanning $k$ -tree of $G$ is a spanning tree with the maximum degree at most $k$ , and a spanning $k$ -ended-tree of $G$ is a spanning tre…

math.CO2024

The existence of a spanning tree with leaf distance at least $d$ and leaf degree at most $k$ via the size or the spectral radius with respect to the minimum degree

Jifu Lin, Lihua You

Let $k$ , $d$ be a positive integer, $G$ be a connected graph of order $n$ , $T$ be a tree. The leaf distance of a tree is defined as the minimum distance between any two leaves. For…

math.CO2024

Connected graphs with large multiplicity of $- 1$ in the spectrum of the eccentricity matrix

Xinghui Zhao, Lihua You

The eccentricity matrix of a simple connected graph is obtained from the distance matrix by only keeping the largest distances for each row and each column, whereas the remaining e…

Edge and spectral conditions for rainbow bipancyclicity in bipartite graph collections

Edge and spectral conditions for rainbow pancyclicity in graph collections

Two problems on booksize and triangular edges in Nosal graphs

The maximum number of cycles of a given length in a nonhamiltonian graph

The signless Laplacian spectral radius of graphs without disjoint cliques

The saturation number of Kts​

Saturation numbers of K2​∨Pk​

On the characterizations of Dk​\Dk−2​

Oriented diameter of graphs with diameter 4 and given edge girth

The connectedness of friends-and-strangers graphs about graph parameters and others

Spectral conditions for spanning k-trees or k-ended-trees of t-connected graphs

The existence of a spanning tree with leaf distance at least d and leaf degree at most k via the size or the spectral radius with respect to the minimum degree

Connected graphs with large multiplicity of −1 in the spectrum of the eccentricity matrix

The saturation number of $K_{t}^{s}$

Saturation numbers of $K_{2} \lor P_{k}$

On the characterizations of $D_{k} \ D_{k - 2}$

Oriented diameter of graphs with diameter $4$ and given edge girth

Spectral conditions for spanning $k$ -trees or $k$ -ended-trees of $t$ -connected graphs

The existence of a spanning tree with leaf distance at least $d$ and leaf degree at most $k$ via the size or the spectral radius with respect to the minimum degree

Connected graphs with large multiplicity of $- 1$ in the spectrum of the eccentricity matrix