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Related papers: Relative Tur\'an densities of ordered graphs

200 papers

We discuss various aspects of the statistical formulation of the theory of random graphs, with emphasis on results obtained in a series of our recent publications.

Statistical Mechanics · Physics 2009-11-10 Zdzislaw Burda , Jerzy Jurkiewicz , Andre Krzywicki

For a graph $H$, the {\em extremal number} $ex(n,H)$ is the maximum number of edges in a graph of order $n$ not containing a subgraph isomorphic to $H$. Let $\delta(H)>0$ and $\Delta(H)$ denote the minimum degree and maximum degree of $H$,…

Combinatorics · Mathematics 2014-04-07 Noga Alon , Raphael Yuster

The generalized Tur\'an problem $ext(n,T,F)$ is to determine the maximal number of copies of a graph $T$ that can exist in an $F$-free graph on $n$ vertices. Recently, Gerbner and Palmer noted that the solution to the generalized Tur\'an…

Combinatorics · Mathematics 2021-12-07 Kyle Murphy , JD Nir

We develop a theory to measure the variance and covariance of probability distributions defined on the nodes of a graph, which takes into account the distance between nodes. Our approach generalizes the usual (co)variance to the setting of…

Physics and Society · Physics 2021-08-19 Karel Devriendt , Samuel Martin-Gutierrez , Renaud Lambiotte

We introduce the Density Formula for (topological) drawings of graphs in the plane or on the sphere, which relates the number of edges, vertices, crossings, and sizes of cells in the drawing. We demonstrate its capability by providing…

We show that the set $\Pi^{(k)}$ of Tur\'an densities of $k$-uniform hypergraphs has infinitely many accumulation points in $[0,1)$ for every $k \geq 3$. This extends an earlier result of ours showing that $\Pi^{(k)}$ has at least one such…

Combinatorics · Mathematics 2025-06-04 David Conlon , Bjarne Schülke

Let $H_n$ be a $k$-graph on $n$ vertices. For $0 \le \ell <k$ and an $\ell$-subset $T$ of $V(H_n)$, define the degree $\deg(T)$ of $T$ to be the number of $(k-\ell)$-subsets~$S$ such that $S \cup T$ is an edge in~$H_n$. Let the minimum…

Combinatorics · Mathematics 2014-10-15 Allan Lo , Klas Markström

We give upper bounds on the order of the automorphism group of a simple graph

Combinatorics · Mathematics 2007-05-23 Ilia Krasikov , Arie Lev , Bhalchandra D. Thatte

This paper summarizes our latest understanding and results about the application of the Mathematics Of Enumeration to Tanner Graphs that have a regular structure called Balanced Tanner Graphs. Some preliminaries of permutation groups have…

Information Theory · Computer Science 2013-01-01 Vivek S Nittoor , Reiji Suda

In this paper, we study the signed domination numbers of graphs and present new sharp lower and upper bounds for this parameter. As an example, we present a lower bound on signed domination number of trees in terms of the order, leaves and…

Combinatorics · Mathematics 2019-08-27 S. M. Hosseini Moghaddam , Abdollah Khodkar , Babak Samadi

In this paper we will provide an introductory understanding of random graph models, and matchings in the case of Erdos-Renyi random graphs. We will provide a synthesis of background theory to this end. We will further examine pertinent…

Statistics Theory · Mathematics 2019-11-18 Lucas Rooney

In this short note we consider the oriented vertex Tur\'an problem in the hypercube: for a fixed oriented graph $\overrightarrow{F}$, determine the maximum size $ex_v(\overrightarrow{F}, \overrightarrow{Q_n})$ of a subset $U$ of the…

Combinatorics · Mathematics 2018-07-19 Dániel Gerbner , Abhishek Methuku , Dániel T. Nagy , Balázs Patkós , Máté Vizer

This paper is motivated by the question of how global and dense restriction sets in results from extremal combinatorics can be replaced by less global and sparser ones. The result we consider here as an example is Turan's theorem, which…

Combinatorics · Mathematics 2017-07-31 Peter Allen , Julia Böttcher , Jan Hladký , Diana Piguet

We study thresholds for extremal properties of random discrete structures. We determine the threshold for Szemer\'edi's theorem on arithmetic progressions in random subsets of the integers and its multidimensional extensions and we…

Combinatorics · Mathematics 2016-09-20 Mathias Schacht

In this note, we revisit a classical problem related to the density of nonlinear statistics. We obtain a new representation of densities and, for the first time, a necessary and sufficient condition for the existence of densities is…

Probability · Mathematics 2021-05-19 Nguyen Tien Dung

We give formulas for the density of the measure of orthogonality for orthonormal polynomials with unbounded recurrence coefficients. The formulas involve limits of appropriately scaled Tur\'an determinants or Christoffel functions. Exact…

Classical Analysis and ODEs · Mathematics 2017-02-07 Grzegorz Świderski

In this paper, we define several measures induced by a finite directed graph. The study themselves is interesting ont only in the noncommutative probability point of view but also in the algebraic structure point of view, since to define…

Probability · Mathematics 2007-05-23 Ilwoo Cho

We examine the chromatic index of generalized truncations of graphs and multigraphs.

Combinatorics · Mathematics 2021-09-15 Brian Alspach , Aditya Joshi

In this paper, we study the signed total domination number in graphs and present new sharp lower and upper bounds for this parameter. For example by making use of the classic theorem of Turan, we present a sharp lower bound on this…

Combinatorics · Mathematics 2019-08-27 S. M. Hosseini Moghaddam , D. A. Mojdeh , Babak Samadi , L. Volkmann

For two graphs $G$ and $H$, the Tur\'{a}n number $ex(G,H)$ is the maximum number of edges in a subgraph of $G$ that contains no copy of $H$. Chen, Li, and Tu determined the Tur\'{a}n numbers $ex(K_{m,n},kK_2)$ for all $k\geq 1$ [7]. In this…

Combinatorics · Mathematics 2017-09-06 Jessica De Silva , Kristin Heysse , Adam Kapilow , Anna Schenfisch , Michael Young