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Related papers: New measures of graph irregularity

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In this work, we give the sharp upper bound for the number of cliques in graphs with bounded odd circumferences. This generalized Tur\'an-type result is an extension of the celebrated Erd\H{o}s and Gallai theorem and a strengthening of…

Combinatorics · Mathematics 2022-12-07 Zequn Lv , Ervin Győri , Zhen He , Nika Salia , Chuanqi Xiao , Xiutao Zhu

The proper chromatic number $\Vec{\chi}(G)$ of a graph $G$ is the minimum $k$ such that there exists an orientation of the edges of $G$ with all vertex-outdegrees at most $k$ and such that for any adjacent vertices, the outdegrees are…

Combinatorics · Mathematics 2022-12-09 Yaobin Chen , Bojan Mohar , Hehui Wu

Uncertainty principles present an important theoretical tool in signal processing, as they provide limits on the time-frequency concentration of a signal. In many real-world applications the signal domain has a complicated irregular…

Information Theory · Computer Science 2023-06-29 Elizaveta Rebrova , Palina Salanevich

We identify three 3-graphs on five vertices each missing in all known extremal configurations for Turan's (3,4)-problem and prove Turan's conjecture for 3-graphs that are additionally known not to contain any induced copies of these…

Combinatorics · Mathematics 2012-10-18 Alexander Razborov

We consider unavoidable chromatic patterns in $2$-colorings of the edges of the complete graph. Several such problems are explored being a junction point between Ramsey theory, extremal graph theory (Tur\'an type problems), zero-sum Ramsey…

Combinatorics · Mathematics 2019-04-09 Yair Caro , Adriana Hansberg , Amanda Montejano

We study topological Poincar\'e type inequalities on general graphs. We characterize graphs satisfying such inequalities and then turn to the best constants in these inequalities. Invoking suitable metrics we can interpret these constants…

Functional Analysis · Mathematics 2018-01-30 Daniel Lenz , Marcel Schmidt , Peter Stollmann

Our purpose is to show that complements of line graphs enjoy nice coloring properties. We show that for all graphs in this class the local and usual chromatic numbers are equal. We also prove a sufficient condition for the chromatic number…

Combinatorics · Mathematics 2020-04-07 Hamid Reza Daneshpajouh , Frédéric Meunier , Guilhem Mizrahi

This paper gives tight upper bounds on the number of edges and the index for $\mathcal{K}^-_{r + 1}$-free unbalanced signed graphs, where $\mathcal{K}^-_{r + 1}$ is the set of $r+1$-vertices unbalanced signed complete graphs. \indent We…

Combinatorics · Mathematics 2023-11-28 Zhuang Xiong , Yaoping Hou

In this paper arithmetic progressions on the integers and the integers modulo n are extended to graphs. This allows for the definition of the anti-van der Waerden number of a graph. Much of the focus of this paper is on 3-term arithmetic…

We prove a generalised Ramsey--Tur\'an theorem for matchings, which (a) simultaneously generalises the Cockayne--Lorimer Theorem (Ramsey for matchings) and the Erd\H{o}s--Gallai Theorem (Tur\'an for matchings), and (b) is a generalised…

Combinatorics · Mathematics 2025-09-16 Peter Keevash , Peleg Michaeli

We introduce a new method for computing bounds on the independence number and fractional chromatic number of classes of graphs with local constraints, and apply this method in various scenarios. We establish a formula that generates a…

Combinatorics · Mathematics 2021-07-26 François Pirot , Jean-Sébastien Sereni

The purpose of this paper is to analyze the degree index and clustering index in random graphs. The degree index in our setup is a certain measure of degree irregularity whose basic properties are well studied in the literature, and the…

Probability · Mathematics 2026-03-11 Ümit Işlak , Barış Yeşiloğlu

Motivated by algorithmic applications, Kun, O'Brien, Pilipczuk, and Sullivan introduced the parameter linear chromatic number as a relaxation of treedepth and proved that the two parameters are polynomially related. They conjectured that…

Combinatorics · Mathematics 2026-03-12 Claire Hilaire , Matjaž Krnc , Martin Milanič , Jean-Florent Raymond

A locally irregular graph is a graph whose adjacent vertices have distinct degrees, a regular graph is a graph where each vertex has the same degree and a locally regular graph is a graph where for every two adjacent vertices u, v, their…

Discrete Mathematics · Computer Science 2018-01-30 Arash Ahadi , Ali Dehghan , Mohammad-Reza Sadeghi , Brett Stevens

In the paper we state and prove theorem describing the upper bound on number of the graphs that have fixed number of vertices |V| and can be colored with the fixed number of n colors. The bound relates both numbers using power of 2, while…

Combinatorics · Mathematics 2007-05-23 Kamil Kulesza , Zbigniew Kotulski

In this thesis we consider ordered graphs (that is, graphs with a fixed linear ordering on their vertices). We summarize and further investigations on the number of edges an ordered graph may have while avoiding a fixed forbidden ordered…

Discrete Mathematics · Computer Science 2009-07-16 Craig Weidert

Here we consider the hypergraph Tur\'an problem in uniformly dense hypergraphs as was suggested by Erd\H{o}s and S\'os. Given a $3$-graph $F$, the uniform Tur\'an density $\pi_u(F)$ of $F$ is defined as the supremum over all $d\in[0,1]$ for…

Combinatorics · Mathematics 2025-10-15 August Y. Chen , Bjarne Schülke

We study the problem of detecting the presence of an underlying high-dimensional geometric structure in a random graph. Under the null hypothesis, the observed graph is a realization of an Erd\H{o}s-R\'enyi random graph $G(n,p)$. Under the…

Statistics Theory · Mathematics 2015-11-24 Sébastien Bubeck , Jian Ding , Ronen Eldan , Miklós Rácz

It is shown that for any fixed $c \geq 3$ and $r$, the maximum possible chromatic number of a graph on $n$ vertices in which every subgraph of radius at most $r$ is $c$ colorable is $\tilde{\Theta}\left(n ^ {\frac{1}{r+1}} \right)$ (that…

Combinatorics · Mathematics 2018-02-01 Noga Alon , Omri Ben-Eliezer

An edge irregular total $k$-labelling $f : V(G)\cup E(G)\rightarrow \{1,2,\dots,k\}$ of a graph $G$ is a labelling of the vertices and the edges of $G$ in such a way that any two different edges have distinct weights. The weight of an edge…

Combinatorics · Mathematics 2023-11-28 Irwansyah , Salman A. N. M