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Related papers: On critical and maximal digraphs

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We consider the strongly connected components (SCCs) of a uniform directed graph on $n$ vertices with i.i.d. in- and out-degree pairs distributed as $(D^-,D^+)$, with $\mathbb E[D^+]=\mathbb E[D^-]=\mu$. We condition on equal total in- and…

Probability · Mathematics 2021-11-03 Serte Donderwinkel , Zheneng Xie

This paper presents a sharp upper bound for the spectral radius of simple digraphs with described number of arcs. Further, the extremal graphs which attain the maximum spectral radius among all simple digraphs with fixed arcs are…

Combinatorics · Mathematics 2015-09-25 Ya-Lei Jin , Xiao-Dong Zhang

We describe structural properties of strongly connected finite directed graphs, that are invariants of the topological conjugacy of their Markov-Dyck shifts. For strongly connected finite directed graphs with these properties topological…

Dynamical Systems · Mathematics 2019-06-11 Toshihiro Hamachi , Wolfgang Krieger

Consider the family of all finite graphs with maximum degree $\Delta(G)<d$ and matching number $\nu(G)<m$. In this paper we give a new proof to obtain the exact upper bound for the number of edges in such graphs and also characterize all…

Combinatorics · Mathematics 2007-05-23 Niranjan Balachandran , Niraj Khare

In this paper we define critical graphs as minimal graphs that support a given set of rates for the index coding problem, and study them for both the one-shot and asymptotic setups. For the case of equal rates, we find the critical graph…

Information Theory · Computer Science 2014-04-15 Mehrdad Tahmasbi , Amirbehshad Shahrasbi , Amin Gohari

Directed graphs are widely used in modelling of nonsymmetric relations in various sciences and engineering disciplines. We discuss invariants of strongly connected directed graphs - minimal number of vertices or edges necessary to remove to…

Discrete Mathematics · Computer Science 2016-10-21 Peteris Daugulis

This article presents the precise asymptotical distribution of two types of critical transmission radii, defined in terms of $k-$connectivity and the minimum vertex degree, for a random geometry graph distributed over a unit-volume region…

Probability · Mathematics 2025-07-17 Jie Ding , Xiang Wei , Shuai Ma

We construct measures of maximal $u$-entropy for any partially hyperbolic diffeomorphism that factors over an Anosov torus automorphism and has mostly contracting center direction. The space of such measures has a finite dimension, and its…

Dynamical Systems · Mathematics 2020-11-06 Raul Ures , Marcelo Viana , Fan Yang , Jiagang Yang

The structure of the character degree graphs $\Delta(G)$, i.e. the prime graphs on the set $\mathrm{cd}(G)$ of the irreducible character degrees of a finite group $G$, such that $G$ is solvable and $\Delta(G)$ has diameter three, remains an…

Group Theory · Mathematics 2024-03-01 Silvio Dolfi , Roghayeh Hafezieh , Pablo Spiga

Let $\overrightarrow{P_k}$ and $\overrightarrow{C_k}$ denote the directed path and the directed cycle of order $k$, respectively. In this paper, we determine the precise maximum size of $\overrightarrow{P_k}$-free digraphs of order $n$ as…

Combinatorics · Mathematics 2021-02-23 Wenling Zhou , Binlong Li

For polynomials and rational maps of fixed degree over a finite field, we bound both the average number of connected components of their functional graphs as well as the average number of periodic points of their associated dynamical…

Dynamical Systems · Mathematics 2014-07-01 Ryan Flynn , Derek Garton

Here we look at (collections of) semimetrics and seminorms, including their ultrametric versions. In particular, we are concerned with geometric properties related to connectedness and topological dimension 0.

Classical Analysis and ODEs · Mathematics 2015-06-25 Stephen Semmes

We characterize the strong metric dimension of the power graph of a finite group. As applications, we compute the strong metric dimension of the power graph of a cyclic group, an abelian group, a dihedral group or a generalized quaternion…

Combinatorics · Mathematics 2016-10-04 Xuanlong Ma , Min Feng , Kaishun Wang

In this paper, the extremal graph with the maximum RRD-value among all the graphs of order n with given cut vertices or edges is characterized. In addition, an upper bounds on the reciprocal degree distance in terms of the number of cut…

Combinatorics · Mathematics 2015-03-12 Xiao-Xin Li

In this paper we study the complementarity spectrum of digraphs, with special attention to the problem of digraph characterization through this complementarity spectrum. That is, whether two non-isomorphic digraphs with the same number of…

Combinatorics · Mathematics 2021-10-11 Diego Bravo , Florencia Cubría , Marcelo Fiori , Vilmar Trevisan

Bounds on the minimum degree and on the number of vertices at- taining it have been much studied for finite edge-/vertex-minimally k- connected/k-edge-connected graphs. We give an overview of the results known for finite graphs, and show…

Combinatorics · Mathematics 2015-03-18 Maya Stein

This paper deals with the maximum value of the difference between the determining number and the metric dimension of a graph as a function of its order. Our technique requires to use locating-dominating sets, and perform an independent…

Combinatorics · Mathematics 2014-01-16 Delia Garijo , Antonio González , Alberto Márquez

Let $G$ be a finite solvable group and let $\Delta(G)$ be the character degree graph of $G$. In this paper, we obtain the metric dimension of certain character degree graphs. Specifically, we calculate the metric dimension for a regular…

Group Theory · Mathematics 2024-11-26 Peter J. Cameron , G. Sivanesan , C. Selvaraj , T. Tamizh Chelvam , Jacob Laubacher

We give a survey of recent results related to the problem of characterizing finite-dimensional division algebras by the set of isomorphism classes of their maximal subfields. We also discuss various generalizations of this problem and some…

Rings and Algebras · Mathematics 2015-06-11 Vladimir I. Chernousov , Andrei S. Rapinchuk , Igor A. Rapinchuk

We study limits of the largest connected components (viewed as metric spaces) obtained by critical percolation on uniformly chosen graphs and configuration models with heavy-tailed degrees. For rank-one inhomogeneous random graphs, such…

Probability · Mathematics 2020-05-11 Shankar Bhamidi , Souvik Dhara , Remco van der Hofstad , Sanchayan Sen