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Related papers: Cacti with maximum Kirchhoff index

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Let $G$ be a connected graph. The resistance distance between two vertices $u$ and $v$ of $G$, denoted by $R_{G}[u,v]$, is defined as the net effective resistance between them in the electric network constructed from $G$ by replacing each…

Combinatorics · Mathematics 2024-06-21 Wensheng Sun , Yujun Yang , Wuxian Chen , Shou-Jun Xu

The eccentricity of a vertex $v$ in a graph $G$ is the maximum distance between $v$ and any other vertex of $G$. The diameter of a graph $G$ is the maximum eccentricity of a vertex in $G$. The eccentric connectivity index of a connected…

Discrete Mathematics · Computer Science 2024-03-11 Pierre Hauweele , Alain Hertz , Hadrien Mélot , Bernard Ries , Gauvain Devillez

Motivated by the notion of resistance distance on graph, we define a new resistance distance between two states on a given finite ergodic Markov chain based on its fundamental matrix. We prove a few equivalent formulations and discuss its…

Probability · Mathematics 2019-03-05 Michael C. H. Choi

The Steiner distance of vertices in a set $S$ is the minimum size of a connected subgraph that contain these vertices. The sum of the Steiner distances over all sets $S$ of cardinality $k$ is called the Steiner $k$-Wiener index and studied…

Combinatorics · Mathematics 2020-08-06 Jie Zhang , Hua Wang , Xiao-Dong Zhang

The general sum-connectivity index of a graph $G$ is defined as $\chi_\alpha(G)=\sum\limits_{uv\in E(G)} {(d(u)+d(v))^{\alpha}}$, where $d(v)$ denotes the degree of the vertex $v$ in $G$ and $\alpha$ is a real number. In this paper it is…

Combinatorics · Mathematics 2018-07-13 M. K. Jamil , I. Tomescu

Dinits, Karzanov and Lomonosov showed that the minimal edge cuts of a finite graph have the structure of a cactus, a tree-like graph constructed from cycles. Evangelidou and Papasoglu extended this to minimal cuts separating the ends of an…

Combinatorics · Mathematics 2015-12-09 Gareth R. Wilkes

A subset $D\subseteq V(G)$ is called a $k$-distance dominating set of $G$ if every vertex in $V(G)\setminus D$ is within distance $k$ from some vertex of $D$. The minimum cardinality among all $k$-distance dominating sets of $G$ is called…

Combinatorics · Mathematics 2018-05-04 D. A. Mojdeh , S. R. Musawi , E. Nazari

Being motivated in terms of mathematical concepts from the theory of electrical networks, Klein & Ivanciuc introduced and studied a new graph-theoretic cyclicity index--the global cyclicity index (Graph cyclicity, excess conductance, and…

Combinatorics · Mathematics 2013-03-05 Yujun Yang

Dinits-Karzanov-Lomonosov showed that it is possible to encode all minimal edge cuts of a graph by a tree-like structure called a cactus. We show here that minimal edge cuts separating ends of the graph rather than vertices can be `encoded'…

Combinatorics · Mathematics 2011-10-25 Anastasia Evangelidou , Panos Papasoglu

Let $r(u,v)$ be the resistance distance between two vertices $u, v$ of a simple graph $G$, which is the effective resistance between the vertices in the corresponding electrical network constructed from $G$ by replacing each edge of $G$…

Combinatorics · Mathematics 2016-06-07 Jia-Bao Liu , Si-Qi Zhangb , Xiang-Feng Pan , Shaohui Wang , Sakander Hayat

A strongly connected digraph is called a cactoid-type if each of its blocks is a digraph consisting of finitely many oriented cycles sharing a common directed path. In this article, we find the formula for the determinant of the distance…

Combinatorics · Mathematics 2020-09-25 Joyentanuj Das , Sumit Mohanty

A distance graph is an undirected graph on the integers where two integers are adjacent if their difference is in a prescribed distance set. The independence ratio of a distance graph $G$ is the maximum density of an independent set in $G$.…

Combinatorics · Mathematics 2014-01-29 James M. Carraher , David Galvin , Stephen G. Hartke , A. J. Radcliff , Derrick Stolee

A close relation between hitting times of the simple random walk on a graph, the Kirchhoff index, resistance-centrality, and related invariants of unicyclic graphs is displayed. Combining with the graph transformations and some other…

Combinatorics · Mathematics 2017-07-10 Jing Huang , Shuchao Li , Zheng Xie

The prism over a graph $G$ is the Cartesian product of $G$ with the complete graph $K_2$. $G$ is prism-hamiltonian if the prism over $G$ has a Hamilton cycle. A good even cactus is a connected graph in which every block is either an edge or…

Combinatorics · Mathematics 2021-07-30 On-Hei Solomon Lo

The Wiener index of a connected graph is the summation of all distances between unordered pairs of vertices of the graph. In this paper, we give an upper bound on the Wiener index of a $k$-connected graph $G$ of order $n$ for integers…

Combinatorics · Mathematics 2018-11-08 Zhongyuan Che , Karen L. Collins

Let $G$ be a connected graph, and let $b$ and $k$ be two positive integers with $b\equiv1$ (mod 2). A $[1,b]$-odd factor of $G$ is a spanning subgraph $F$ of $G$ with $d_F(v)\equiv1$ (mod 2) and $1\leq d_F(v)\leq b$ for every $v\in V(G)$. A…

Combinatorics · Mathematics 2026-01-14 Sufang Wang , Wei Zhang

The circumference $c(G)$ of a graph $G$ is the length of a longest cycle. By exploiting our recent results on resistance of snarks, we construct infinite classes of cyclically $4$-, $5$- and $6$-edge-connected cubic graphs with…

Discrete Mathematics · Computer Science 2013-11-12 Edita Máčajová , Ján Mazák

A Kirchhoff graph is a vector graph with orthogonal cycles and vertex cuts. An algorithm has been developed that constructs all the Kirchhoff graphs up to a fixed edge multiplicity. This algorithm is used to explore the structure of prime…

Combinatorics · Mathematics 2022-07-26 Jessica Wang , Joseph Fehribach

A star edge coloring of a graph $G$ is a proper edge coloring of $G$ such that no path or cycle of length four is bi-colored. The star chromatic index of $G$, denoted by $\chi^{\prime}_{s}(G)$, is the minimum $k$ such that $G$ admits a star…

Combinatorics · Mathematics 2019-11-07 Behnaz Omoomi , Marzieh Vahid Dastjerdi , Yasaman Yektaeian

Building upon the notion of Gutman index $\operatorname{SGut}(G)$, Mao and Das recently introduced the Steiner Gutman index by incorporating Steiner distance for a connected graph $G$. The \emph{Steiner Gutman $k$-index}…

Combinatorics · Mathematics 2021-07-14 Zhao Wang , Yaping Mao , Kinkar Chandra Das , Yilun Shang
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