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

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28 papers · 1 filter

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

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…

math.CO2011

Oriented diameter and rainbow connection number of a graph

Xiaolong Huang, Hengzhe Li, Xueliang Li +1

The oriented diameter of a bridgeless graph $G$ is $min {d iam (H) ∣ H i s an or i e n t a t i o n o f G}$ . A path in an edge-colored graph $G$ , where adjacent edges may have the same co…

math.CO2011★ 54 cited

On the generalized (edge-)connectivity of graphs

Xueliang Li, Yaping Mao, Yuefang Sun

The generalized $k$ -connectivity $κ_{k} (G)$ of a graph $G$ was introduced by Chartrand et al. in 1984. It is natural to introduce the concept of generalized $k$ -edge-connectivity $λ_…

math.CO2011★ 4 cited

Upper bound for the rainbow connection number of bridgeless graphs with diameter 3

Hengzhe Li, Xueliang Li, Yuefang Sun

A path in an edge-colored graph $G$ , where adjacent edges may have the same color, is called rainbow if no two edges of the path are colored the same. The rainbow connection number…

math.CO2011

Note on the oriented diameter of graphs with diameter 3

Hengzhe Li, Xueliang Li, Yuefang Sun +1

In 1978, Chvátal and Thomassen showed that every bridgeless graph with diameter 2 has an orientation with diameter at most 6. They also gave general bounds on the smallest value $f…

math.CO2011

Asymptotic value of the minimal size of a graph with rainbow connection number 2

Hengzhe Li, Xueliang Li, Yuefang Sun

A path in an edge (vertex)-colored graph $G$ , where adjacent edges (vertices) may have the same color, is called a rainbow path if no pair of edges (internal vertices) of the path…

math.CO2011★ 19 cited

The generalized 3-connectivity of Cartesian product graphs

Hengzhe Li, Xueliang Li, Yuefang Sun

The generalized connectivity of a graph, which was introduced recently by Chartrand et al., is a generalization of the concept of vertex connectivity. Let $S$ be a nonempty set of…

math.CO2011★ 8 cited

Rainbow connections of graphs -- A survey

Xueliang Li, Yuefang Sun

The concept of rainbow connection was introduced by Chartrand et al. in 2008. It is fairly interesting and recently quite a lot papers have been published about it. In this survey…

math.CO2010★ 8 cited

Rainbow connection numbers of complementary graphs

Xueliang Li, Yuefang Sun

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…

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

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

Note on minimally k-rainbow connected graphs

Graphs with large generalized 3-connectivity

Oriented diameter and rainbow connection number of a graph

On the generalized (edge-)connectivity of graphs

Upper bound for the rainbow connection number of bridgeless graphs with diameter 3

Note on the oriented diameter of graphs with diameter 3

Asymptotic value of the minimal size of a graph with rainbow connection number 2

The generalized 3-connectivity of Cartesian product graphs

Rainbow connections of graphs -- A survey

Rainbow connection numbers of complementary graphs

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

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

Note on minimally $k$ -rainbow connected graphs