Yuefang Sun

activity

20092022

most citedOn the generalized (edge-)connectivity of graphs

54 citations · 110 across the 36 of their papers we have counts for

collaborators

36 papers

math.CO2022

Directed Steiner path packing and directed path connectivity

Yuefang Sun

For a digraph $D = (V (D), A (D))$ , and a set $S \subseteq V (D)$ with $r \in S$ and $∣ S ∣ \geq 2$ , a directed $(S, r)$ -Steiner path or, simply, an $(S, r)$ -path is a directed path $P$ star…

math.CO2022

A minimum semi-degree condition for unpaired many-to-many disjoint path covers in digraphs

Ansong Ma, Yuefang Sun

For a digraph $D$ , let $δ^{0} (D) = min {δ^{+} (D), δ^{-} (D)}$ be the minimum semi-degree of $D$ . A set of $k$ vertex-disjoint paths, ${P_{1}, \dots, P_{k}}$ , joining a disjoint…

math.CO2022

Sharp Bounds and Precise Values for the $N_{i}$ -Chromatic Number of Graphs

Yangfan Yu, Yuefang Sun

Let $G$ be a connected undirected graph.~A vertex coloring $f$ of $G$ is an $N_{i}$ -vertex coloring if for each vertex $x$ in $G$ , the number of different colors assigned to $N_{G} (x)$ …

math.CO2022

A minimum semi-degree sufficient condition for one-to-many disjoint path covers in semicomplete digraphs

Ansong Ma, Yuefang Sun, Xiaoyan Zhang

Let $D$ be a digraph. We define the minimum semi-degree of $D$ as $δ^{0} (D) := min {δ^{+} (D), δ^{-} (D)}$ . Let $k$ be a positive integer, and let $S = {s}$ and $T = \{t_{1}, \d…

math.CO2022

Perfect Out-forests and Steiner Cycle Packing in Digraphs

Yuefang Sun

In this paper, we study the complexity of two types of digraph packing problems: perfect out-forests problem and Steiner cycle packing problem. For the perfect out-forest problem,…

math.CO2022

Steiner Type Packing Problems in Digraphs: A Survey

Yuefang Sun

Graph packing problem is one of the central problems in graph theory and combinatorial optimization. The famous Steiner tree packing problem in undirected graphs has become an well…

math.CO2022

Strong subgraph 2-arc-connectivity and arc-strong connectivity of Cartesian product of digraphs

Yiling Dong, Gregory Gutin, Yuefang Sun

Let $D = (V, A)$ be a digraph of order $n$ , $S$ a subset of $V$ of size $k$ and $2 \leq k \leq n$ . A strong subgraph $H$ of $D$ is called an $S$ -strong subgraph if $S \subseteq V (H)$ . A p…

math.CO2021

Packing Strong Subgraph in Digraphs

Yuefang Sun, Gregory Gutin, Xiaoyan Zhang

In this paper, we study two types of strong subgraph packing problems in digraphs, including internally disjoint strong subgraph packing problem and arc-disjoint strong subgraph pa…

math.CO2021★ 1 cited

Compositions of Digraphs: A Survey

Yuefang Sun

In this survey we overview known results and get several new results on digraph compositions which generalize several classes of digraphs, such as quasi-transitive digraphs. After…

math.CO2020

Extremal results for directed tree connectivity

Yuefang Sun

For a digraph $D = (V (D), A (D))$ , and a set $S \subseteq V (D)$ with $r \in S$ and $∣ S ∣ \geq 2$ , an $(S, r)$ -tree is an out-tree $T$ rooted at $r$ with $S \subseteq V (T)$ . Two $(S, r)$ -tr…

math.CO2020

Kings and Kernels in Semicomplete Compositions

Yuefang Sun, Zemin Jin

Let $k$ be an integer with $k \geq 2$ . A $k$ -king in a digraph $D$ is a vertex which can reach every other vertex by a directed path of length at most $k$ and a non-king is a vertex…

math.CO2020

Semicomplete Compositions of Digraphs

Yuefang Sun

Let $T$ be a digraph with vertices $u_{1}, \dots, u_{t}$ ( $t \geq 2$ ) and let $H_{1}, \dots, H_{t}$ be digraphs such that $H_{i}$ has vertices $u_{i, j_{i}}, 1 \leq j_{i} \leq n_{i} .$ Then the compositi…

math.CO2020

Directed Steiner tree packing and directed tree connectivity

Yuefang Sun, Anders Yeo

cs.DM2019

Arc-disjoint in- and out-branchings rooted at the same vertex in compositions of digraphs

Gregory Gutin, Yuefang Sun

A digraph $D = (V, A)$ has a good pair at a vertex $r$ if $D$ has a pair of arc-disjoint in- and out-branchings rooted at $r$ . Let $T$ be a digraph with $t$ vertices $u_1,\dots , u_t…

cs.DM2019

Extremality and Sharp Bounds for the $k$ -edge-connectivity of Graphs

Yuefang Sun, Xiaoyan Zhang, Zhao Zhang

Boesch and Chen (SIAM J. Appl. Math., 1978) introduced the cut-version of the generalized edge-connectivity, named $k$ -edge-connectivity. For any integer $k$ with $2 \leq k \leq n$ ,…

cs.DM2018

Arc-disjoint strong spanning subdigraphs in compositions and products of digraphs

Yuefang Sun, Gregory Gutin, Jiangdong Ai

A digraph $D = (V, A)$ has a good decomposition if $A$ has two disjoint sets $A_{1}$ and $A_{2}$ such that both $(V, A_{1})$ and $(V, A_{2})$ are strong. Let $T$ be a digraph with $t$ vertices…

cs.DM2018★ 1 cited

Strong Subgraph Connectivity of Digraphs: A Survey

Yuefang Sun, Gregory Gutin

In this survey we overview known results on the strong subgraph $k$ -connectivity and strong subgraph $k$ -arc-connectivity of digraphs. After an introductory section, the paper is d…

cs.DM2018★ 1 cited

Strong subgraph $k$ -arc-connectivity

Yuefang Sun, Gregory Gutin

Two previous papers, arXiv:1803.00284 and arXiv:1803.00281, introduced and studied strong subgraph $k$ -connectivity of digraphs obtaining characterizations, lower and upper bounds…

cs.DM2018

Strong Subgraph $k$ -connectivity

Yuefang Sun, Gregory Gutin, Anders Yeo +1

Generalized connectivity introduced by Hager (1985) has been studied extensively in undirected graphs and become an established area in undirected graph theory. For connectivity pr…

cs.DM2018★ 1 cited

Strong subgraph $k$ -connectivity bounds

Yuefang Sun, Gregory Gutin

Let $D = (V, A)$ be a digraph of order $n$ , $S$ a subset of $V$ of size $k$ and $2 \leq k \leq n$ . Strong subgraphs $D_{1}, \dots, D_{p}$ containing $S$ are said to be internally disjoint i…

cs.DS2017

An improved kernel for the cycle contraction problem

Bin Sheng, Yuefang Sun

The problem of modifying a given graph to satisfy certain properties has been one of the central topics in parameterized tractability study. In this paper, we study the cycle contr…

math.CO2013

Characterize graphs with rainbow connection number $m - 2$ and $m - 3$

Xueliang Li, Yuefang Sun, Yan Zhao

A path in an edge-colored graph, where adjacent edges may be colored the same, is a rainbow path if no two edges of it are colored the same. A nontrivial connected graph $G$ is rai…

math.CO2012

Note on minimally $k$ -rainbow connected graphs

Hengzhe Li, Xueliang Li, Yuefang Sun +1

An edge-colored graph $G$ , where adjacent edges may have the same color, is {\it rainbow connected} if every two vertices of $G$ are connected by a path whose edge has distinct col…

math.CO2012

Graphs with large generalized 3-connectivity

Hengzhe Li, Xueliang Li, Yaping Mao +1

Let $S$ be a nonempty set of vertices of a connected graph $G$ . A collection $T_{1}, ..., T_{ℓ}$ of trees in $G$ is said to be internally disjoint trees connecting $S$ if $E(T_i)\cap…

Directed Steiner path packing and directed path connectivity

A minimum semi-degree condition for unpaired many-to-many disjoint path covers in digraphs

Sharp Bounds and Precise Values for the Ni​-Chromatic Number of Graphs

A minimum semi-degree sufficient condition for one-to-many disjoint path covers in semicomplete digraphs

Perfect Out-forests and Steiner Cycle Packing in Digraphs

Steiner Type Packing Problems in Digraphs: A Survey

Strong subgraph 2-arc-connectivity and arc-strong connectivity of Cartesian product of digraphs

Packing Strong Subgraph in Digraphs

Compositions of Digraphs: A Survey

Extremal results for directed tree connectivity

Kings and Kernels in Semicomplete Compositions

Semicomplete Compositions of Digraphs

Directed Steiner tree packing and directed tree connectivity

Arc-disjoint in- and out-branchings rooted at the same vertex in compositions of digraphs

Extremality and Sharp Bounds for the k-edge-connectivity of Graphs

Arc-disjoint strong spanning subdigraphs in compositions and products of digraphs

Strong Subgraph Connectivity of Digraphs: A Survey

Strong subgraph k-arc-connectivity

Strong Subgraph k-connectivity

Strong subgraph k-connectivity bounds

An improved kernel for the cycle contraction problem

Characterize graphs with rainbow connection number m−2 and m−3

Note on minimally k-rainbow connected graphs

Graphs with large generalized 3-connectivity

Sharp Bounds and Precise Values for the $N_{i}$ -Chromatic Number of Graphs

Extremality and Sharp Bounds for the $k$ -edge-connectivity of Graphs

Strong subgraph $k$ -arc-connectivity

Strong Subgraph $k$ -connectivity

Strong subgraph $k$ -connectivity bounds

Characterize graphs with rainbow connection number $m - 2$ and $m - 3$

Note on minimally $k$ -rainbow connected graphs