H. Lei

activity

20172026

most citedTotal rainbow connection of digraphs

23 citations · 56 across the 19 of their papers we have counts for

collaborators

20 papers

math.CO2026

Reconfiguration graphs of $K_{2, 3}$ -minor-free graphs

Ruijuan Gu, Hui Lei, Zhaoxiang Li +2

The $ℓ$ -reconfiguration graph of a graph $G$ , denoted by $R_{ℓ} (G)$ , is the graph whose vertices are the proper $ℓ$ -colorings of $G$ , with an edge between two co…

math.CO2024

The Minimum Weighting Ratio Problem and Its Application in Chordal Graphs

Hui Lei, Mei Lu, Yongtang Shi +2

Constructing the maximum spanning tree $T$ of an edge-weighted connected graph $G$ is one of the important research topics in computer science and optimization, and the related res…

math.CO2024

Reconfiguration graphs for vertex colorings of $P_{5}$ -free graphs

Hui Lei, Yulai Ma, Zhengke Miao +2

For any positive integer $k$ , the reconfiguration graph for all $k$ -colorings of a graph $G$ , denoted by $R_{k} (G)$ , is the graph where vertices represent the $k$ -colorings…

math.CO2024

Graph operations and a unified method for kinds of Turán-type problems on paths, cycles and matchings

Jiangdong Ai, Hui Lei, Bo Ning +1

Let $G$ be a connected graph and $P (G)$ a graph parameter. We say that $P (G)$ is feasible if $P (G)$ satisfies the following properties: (I) $\mathcal{…

math.CO2022

Some Mader-perfect graph classes

Hui Lei, Siyan Li, Xiaopan Lian +1

The dichromatic number of $D$ , denoted by $χ (D)$ , is the smallest integer $k$ such that $D$ admits an acyclic $k$ -coloring. We use $ma d e r_{χ} (F)$ to d…

math.CO2022

Weak-odd chromatic index of special digraph classes

Ruijuan Gu, Hui Lei, Xiaopan Lian +1

Give a digraph $D = (V (D), A (D))$ , let $\partial_{D}^{+} (v) = {v w ∣ w \in N_{D}^{+} (v)}$ and $\partial_{D}^{-} (v) = {uv ∣ u \in N_{D}^{-} (v)}$ be semi-cuts of $v$ . A mapping $φ : A (D) \to [k]$ is call…

math.CO2021

On critical graphs for the chromatic edge-stability number

Hui Lei, Xiaopan Lian, Xianhao Meng +2

The {\em chromatic edge-stability number} $e s_{χ} (G)$ of a graph $G$ is the minimum number of edges whose removal results in a spanning subgraph with the chromatic number smaller tha…

math.CO2021

A characterization of 4- $χ_{S}$ -vertex-critical graphs for packing sequences with $s_{1} = 1$ and $s_{2} \geq 3$

Sandi Klavžar, Hui Lei, Xiaopan Lian +1

If $S = (s_{1}, s_{2}, \dots)$ is a non-decreasing sequence of positive integers, then the $S$ -packing $k$ -coloring of a graph $G$ is a mapping $c : V (G) \to [k]$ such that if $c(u)=…

math.CO2020★ 4 cited

A survey on star edge-coloring of graphs

Hui Lei, Yongtang Shi

The star chromatic index of a multigraph $G$ , denoted $χ_{s t}^{'} (G)$ , is the minimum number of colors needed to properly color the edges of $G$ such that no path or cycle of length f…

math.CO2020★ 1 cited

Some extremal results on the chromatic-stability index

Shenwei Huang, Sandi Klavžar, Hui Lei +2

The $χ$ -stability index $es_{χ} (G)$ of a graph $G$ is the minimum number of its edges whose removal results in a graph with the chromatic number smaller than that of $G$ . In th…

math.CO2019

The saturation number of $K_{3, 3}$

Shenwei Huang, Hui Lei, Yongtang Shi +1

A graph $G$ is called $F$ -saturated if $G$ does not contain $F$ as a subgraph (not necessarily induced) but the addition of any missing edge to $G$ creates a copy of $F$ . The satur…

math.CO2018★ 1 cited

Gallai-Ramsey numbers of $C_{10}$ and $C_{12}$

Hui Lei, Yongtang Shi, Zi-Xia Song +1

A Gallai coloring is a coloring of the edges of a complete graph without rainbow triangles, and a Gallai $k$ -coloring is a Gallai coloring that uses $k$ colors. Given an integer $k…

math.CO2018★ 2 cited

On Hypergraph Lagrangians and Frankl-Füredi's Conjecture

Hui Lei, Linyuan Lu

Frankl and Füredi conjectured in 1989 that the maximum Lagrangian, denoted by $λ_{r} (m)$ , among all $r$ -uniform hypergraphs of fixed size $m$ is achieved by the minimum hypergraph $C…

math.CO2018★ 9 cited

On Lagrangians of $3$ -uniform hypergraphs

Hui Lei, Linyuan Lu, Yuejian Peng

Frankl and Füredi conjectured in 1989 that the maximum Lagrangian of all $r$ -uniform hypergraphs of fixed size $m$ is realized by the minimum hypergraph $C_{r, m}$ under the colexic…

math.CO2018

k-Ary spanning trees contained in tournaments

Jiangdong Ai, Hui Lei, Yongtang Shi +2

A rooted tree is called a $k$ -ary tree, if all non-leaf vertices have exactly $k$ children, except possibly one non-leaf vertex has at most $k - 1$ children. Denote by $h (k)$ the min…

math.CO2017

Extremal problems on saturation for the family of $k$ -edge-connected graphs

Hui Lei, Suil O, Yongtang Shi +2

Let $F$ be a family of graphs. A graph $G$ is $F$ -saturated if $G$ contains no member of $F$ as a subgraph but $G + e$ contains some member of $\mathcal…

math.CO2017★ 14 cited

Star 5-edge-colorings of subcubic multigraphs

Hui Lei, Yongtang Shi, Zi-Xia Song +1

The star chromatic index of a multigraph $G$ , denoted $χ_{s}^{'} (G)$ , is the minimum number of colors needed to properly color the edges of $G$ such that no path or cycle of length fo…

math.CO2017★ 23 cited

Total rainbow connection of digraphs

Hui Lei, Henry Liu, Colton Magnant +1

An edge-coloured path is rainbow if its edges have distinct colours. For a connected graph $G$ , the rainbow connection number (resp. strong rainbow connection number) of $G$ is the…

math.CO2017★ 2 cited

Rainbow vertex connection of digraphs

Hui Lei, Shasha Li, Henry Liu +1

An edge-coloured path is \emph{rainbow} if its edges have distinct colours. An edge-coloured connected graph is said to be \emph{rainbow connected} if any two vertices are connecte…

math.CO2017

Star chromatic index of subcubic multigraphs

Hui Lei, Yongtang Shi, Zi-Xia Song

The star chromatic index of a multigraph $G$ , denoted $χ_{s}^{'} (G)$ , is the minimum number of colors needed to properly color the edges of $G$ such that no path or cycle of length fo…

Reconfiguration graphs of K2,3​-minor-free graphs

The Minimum Weighting Ratio Problem and Its Application in Chordal Graphs

Reconfiguration graphs for vertex colorings of P5​-free graphs

Graph operations and a unified method for kinds of Turán-type problems on paths, cycles and matchings

Some Mader-perfect graph classes

Weak-odd chromatic index of special digraph classes

On critical graphs for the chromatic edge-stability number

A characterization of 4-χS​-vertex-critical graphs for packing sequences with s1​=1 and s2​≥3

A survey on star edge-coloring of graphs

Some extremal results on the chromatic-stability index

The saturation number of K3,3​

Gallai-Ramsey numbers of C10​ and C12​

On Hypergraph Lagrangians and Frankl-Füredi's Conjecture

On Lagrangians of 3-uniform hypergraphs

k-Ary spanning trees contained in tournaments

Extremal problems on saturation for the family of k-edge-connected graphs

Star 5-edge-colorings of subcubic multigraphs

Total rainbow connection of digraphs

Rainbow vertex connection of digraphs

Star chromatic index of subcubic multigraphs

Reconfiguration graphs of $K_{2, 3}$ -minor-free graphs

Reconfiguration graphs for vertex colorings of $P_{5}$ -free graphs

A characterization of 4- $χ_{S}$ -vertex-critical graphs for packing sequences with $s_{1} = 1$ and $s_{2} \geq 3$

The saturation number of $K_{3, 3}$

Gallai-Ramsey numbers of $C_{10}$ and $C_{12}$

On Lagrangians of $3$ -uniform hypergraphs

Extremal problems on saturation for the family of $k$ -edge-connected graphs