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Related papers: On jumped Wenger graphs

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A clique transversal in a graph is a set of vertices intersecting all maximal cliques. The problem of determining the minimum size of a clique transversal has received considerable attention in the literature. In this paper, we initiate the…

Combinatorics · Mathematics 2024-08-14 Martin Milanič , Yushi Uno

The maximum number of vertices in a graph of maximum degree $\Delta\ge 3$ and fixed diameter $k\ge 2$ is upper bounded by $(1+o(1))(\Delta-1)^{k}$. If we restrict our graphs to certain classes, better upper bounds are known. For instance,…

Combinatorics · Mathematics 2015-12-14 Eran Nevo , Guillermo Pineda-Villavicencio , David R. Wood

We give upper bounds for the number $\Phi_\ell(G)$ of matchings of size $\ell$ in (i) bipartite graphs $G=(X\cup Y, E)$ with specified degrees $d_x$ ($x\in X$), and (ii) general graphs $G=(V,E)$ with all degrees specified. In particular,…

Combinatorics · Mathematics 2012-05-22 Liviu Ilinca , Jeff Kahn

We present a $(1+\frac{k}{k+2})$-approximation algorithm for the Maximum $k$-dependent Set problem on bipartite graphs for any $k\ge1$. For a graph with $n$ vertices and $m$ edges, the algorithm runs in $O(k m \sqrt{n})$ time and improves…

Combinatorics · Mathematics 2021-10-07 Seyedmohammadhossein Hosseinian , Sergiy Butenko

We propose a random bipartite graph with weights assigned to both parts of the vertex sets. Edges are formed independently with probabilities that depend on these weights. This bipartite graph naturally gives rise to a random intersection…

Probability · Mathematics 2025-06-10 Alastair Haig , Minmin Wang

mim-width is a recent graph width measure that has seen applications in graph algorithms and problems related to propositional satisfiability. In this paper, we show linear lower bounds for the mim-width of strongly chordal split graphs,…

Discrete Mathematics · Computer Science 2017-01-05 Stefan Mengel

In this paper, we investigate how the Wiener index of unicyclic graphs varies with graph operations. These results are used to present a sharp lower bound for the Wiener index of unicyclic graphs of order $n$ with girth and the matching…

Combinatorics · Mathematics 2011-03-01 Ya-Hong Chen , Xiao-Dong Zhang

Twin-width is a recently introduced graph parameter based on the repeated contraction of near-twins. It has shown remarkable utility in algorithmic and structural graph theory, as well as in finite model theory -- particularly since…

Combinatorics · Mathematics 2025-09-11 Irene Heinrich , Ferdinand Ihringer , Simon Raßmann , Lena Volk

A graph is closed when its vertices have a labeling by $[n]$ such that the binomial edge ideal $J_G$ has a quadratic Gr\"{o}bner basis with respect to the lexicographic order induced by $x_1 > \cdots > x_n > y_1> \cdots > y_n$. In this…

Commutative Algebra · Mathematics 2017-08-30 Leila Sharifan , Masoumeh Javanbakht

The concept of graph powers has been extensively studied in graph theory. Analogous to graph powers, Chandran et al. [3] introduced the notion of bipartite powers for bipartite graphs. In this paper, we show that the class of interval…

Combinatorics · Mathematics 2025-09-29 Indrajit Paul , Ashok Kumar Das

A bipartite covering of a (multi)graph $G$ is a collection of bipartite graphs, so that each edge of $G$ belongs to at least one of them. The capacity of the covering is the sum of the numbers of vertices of these bipartite graphs. In this…

Combinatorics · Mathematics 2023-08-01 Noga Alon

We give a simple geometric interpretation of an algebraic construction of Wenger that yields $n$-vertex graphs with no cycle of length $4$, $6$ or $10$ and close to the maximum number of edges.

Combinatorics · Mathematics 2021-02-19 David Conlon

A \textit{diameter graph in $\mathbb R^d$} is a graph, whose set of vertices is a finite subset of $\mathbb R^d$ and whose set of edges is formed by pairs of vertices that are at diameter apart. This paper is devoted to the study of…

Combinatorics · Mathematics 2017-12-01 Andrey Kupavskii

Let $G$ be a finite simple graph and $I(G)$ denote the corresponding edge ideal. For all $s \geq 1$, we obtain upper bounds for reg$(I(G)^s)$ for bipartite graphs. We then compare the properties of $G$ and $G'$, where $G'$ is the graph…

Commutative Algebra · Mathematics 2016-09-07 A V Jayanthan , N Narayanan , S Selvaraja

We study the problem of finding a minimum $k$-critical-bipartite graph of order $(n,m)$: a bipartite graph $G=(U,V;E)$, with $|U|=n$, $|V|=m$, and $n>m>1$, which is $k$-critical-bipartite, and the tuple $(|E|, \Delta_U, \Delta_V)$, where…

Combinatorics · Mathematics 2023-07-17 Sylwia Cichacz , Agieszka Görlich , Karol Suchan

In this article we derive an explicit diameter bound for graphs satisfying the so-called curvature dimension conditions $CD(K,n)$. This refines a recent result due to Liu, M\"unch and Peyerimhoff when the dimension $n$ is finite.

Combinatorics · Mathematics 2024-05-21 Yi C. Huang , Ze Yang

We introduce a new class of countably infinite random geometric graphs, whose vertices are points in a metric space, and vertices are adjacent independently with probability p if the metric distance between the vertices is below a given…

Combinatorics · Mathematics 2012-08-28 Anthony Bonato , Jeannette Janssen

A bipartite graph $G$ is semi-algebraic in $\mathbb{R}^d$ if its vertices are represented by point sets $P,Q \subset \mathbb{R}^d$ and its edges are defined as pairs of points $(p,q) \in P\times Q$ that satisfy a Boolean combination of a…

Combinatorics · Mathematics 2015-11-24 Jacob Fox , János Pach , Adam Sheffer , Andrew Suk , Joshua Zahl

We show that a simple Markov chain, the Glauber dynamics, can efficiently sample independent sets almost uniformly at random in polynomial time for graphs in a certain class. The class is determined by boundedness of a new graph parameter…

Discrete Mathematics · Computer Science 2020-12-07 Martin Dyer , Catherine Greenhill , Haiko Müller

The binding number $b(G)$ of a graph, introduced by Woodall [J. Combin. Theory, Ser. B, 1973], is a central topic of both structural and extremal graph theory. It is closely related to fundamental combinatorial and structural properties of…

Combinatorics · Mathematics 2026-04-20 Ruifang Liu , Hongyu Chen , Ao Fan
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