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Related papers: Two extremal problems in the light of Lex graphs

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We find the maximum number of maximal independent sets in two families of graphs: all graphs with $n$ vertices and at most $r$ cycles, and all such graphs that are also connected. In addition, we characterize the extremal graphs.

Combinatorics · Mathematics 2007-05-23 Chee Ying Goh , Khee Meng Koh , Bruce E. Sagan , V. Vatter

Some problems of statistics can be reduced to extremal problems of minimizing functionals of smooth functions defined on the cube $[0,1]^m$, $m\geq 2$. In this paper, we study a class of extremal problems that is closely connected to the…

Probability · Mathematics 2010-12-06 Alexander Nazarov , Natalia Stepanova

We determine the maximum number of maximal independent sets of arbitrary graphs in terms of their covering numbers and we completely characterize the extremal graphs. As an application, we give a similar result for K\"onig-Egerv\'ary graphs…

Combinatorics · Mathematics 2016-10-20 Do Trong Hoang , Tran Nam Trung

Let $\mathbf{X}(n) \in \mathbb{R}^d$ be a sequence of random vectors, where $n\in\mathbb{N}$ and $d = d(n)$. Under certain weakly dependence conditions, we prove that the distribution of the maximal component of $\mathbf{X}$ and the…

Probability · Mathematics 2025-04-22 Mikhail Isaev , Igor Rodionov , Rui-Ray Zhang , Maksim Zhukovskii

The size of a largest independent set of vertices in a given graph $G$ is denoted by $\alpha(G)$ and is called its independence number (or stability number). Given a graph $G$ and an integer $K,$ it is NP-complete to decide whether…

Combinatorics · Mathematics 2017-09-11 Ingo Schiermeyer

The following natural problem was raised independently by Erd\H{o}s-Hajnal and Linial-Rabinovich in the late 80's. How large must the independence number $\alpha(G)$ of a graph $G$ be whose every $m$ vertices contain an independent set of…

Combinatorics · Mathematics 2023-01-18 Matija Bucić , Benny Sudakov

We systematically study a natural problem in extremal graph theory, to minimize the number of edges in a graph with a fixed number of vertices, subject to a certain local condition: each vertex must be in a copy of a fixed graph $H$. We…

Combinatorics · Mathematics 2020-06-24 Debsoumya Chakraborti , Po-Shen Loh

If $A$ is an independent set of a graph $G$ such that the vertices in $A$ have different degrees, then we call $A$ an irregular independent set of $G$. If $D$ is a dominating set of $G$ such that the vertices that are not in $D$ have…

Combinatorics · Mathematics 2017-06-22 Peter Borg , Yair Caro , Kurt Fenech

We consider numbers and sizes of independent sets in graphs with minimum degree at least $d$, when the number $n$ of vertices is large. In particular we investigate which of these graphs yield the maximum numbers of independent sets of…

Combinatorics · Mathematics 2012-10-05 Hiu-Fai Law , Colin McDiarmid

In this paper we investigate the extremal relationship between two well-studied graph parameters: the order of the largest homogeneous set in a graph $G$ and the maximal number of distinct degrees appearing in an induced subgraph of $G$,…

Combinatorics · Mathematics 2022-12-01 Eoin Long , Laurentiu Ploscaru

We survey recent advances in the theory of graph and hypergraph decompositions, with a focus on extremal results involving minimum degree conditions. We also collect a number of intriguing open problems, and formulate new ones.

Combinatorics · Mathematics 2021-06-28 Stefan Glock , Daniela Kühn , Deryk Osthus

Many problems in extremal graph theory correspond to questions involving homomorphisms into a fixed image graph. Recently, there has been interest in maximizing the number of homomorphisms from graphs with a fixed number of vertices and…

Combinatorics · Mathematics 2016-06-09 Jonathan Cutler , Nicholas Kass

We prove new lower and upper bounds on the higher gonalities of finite graphs. These bounds are generalizations of known upper and lower bounds for first gonality to higher gonalities, including upper bounds on gonality involving…

For a $k$-uniform hypergraph $F$ let $\textrm{ex}(n,F)$ be the maximum number of edges of a $k$-uniform $n$-vertex hypergraph $H$ which contains no copy of $F$. Determining or estimating $\textrm{ex}(n,F)$ is a classical and central problem…

Combinatorics · Mathematics 2020-12-18 Christian Reiher

The study of multivariate extremes is dominated by multivariate regular variation, although it is well known that this approach does not provide adequate distinction between random vectors whose components are not always simultaneously…

Statistics Theory · Mathematics 2021-08-17 Natalia Nolde , Jennifer L. Wadsworth

Packing problems in discrete geometry can be modeled as finding independent sets in infinite graphs where one is interested in independent sets which are as large as possible. For finite graphs one popular way to compute upper bounds for…

Optimization and Control · Mathematics 2021-08-26 David de Laat , Frank Vallentin

We introduce methods to count and enumerate all maximal independent, all maximum independent sets, and all independent sets in threshold graphs and k-threshold graphs. Within threshold graphs and k-threshold graphs independent sets…

Data Structures and Algorithms · Computer Science 2017-10-26 Frank Gurski , Carolin Rehs

Extremal graph theory studies the maximum or minimum number of subgraphs isomorphic to a prescribed graph under given constraints. \textit{Localization} has recently emerged as a framework that refines such problems by assigning extremal…

Combinatorics · Mathematics 2026-03-10 Rajat Adak , L. Sunil Chandran

We explore the dependence structure in the sampled sequence of large networks. We consider randomized algorithms to sample the nodes and study extremal properties in any associated stationary sequence of characteristics of interest like…

Social and Information Networks · Computer Science 2015-02-25 Konstantin Avrachenkov , Natalia M. Markovich , Jithin K. Sreedharan

In this paper, we establish a couple of results on extremal problems in bipartite graphs. Firstly, we show that every sufficiently large bipartite graph with average degree $D$ and with $n$ vertices on each side has a balanced independent…

Combinatorics · Mathematics 2023-06-19 Debsoumya Chakraborti