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Related papers: Computational lower limits on small Ramsey numbers

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We prove upper and lower bounds on the size of the largest square grid graph that is a subgraph, minor, or shallow minor of a graph in the form of a larger square grid from which a specified number of vertices have been deleted. Our bounds…

Discrete Mathematics · Computer Science 2014-08-07 David Eppstein

Graphs are a natural representation of data from various contexts, such as social connections, the web, road networks, and many more. In the last decades, many of these networks have become enormous, requiring efficient algorithms to cut…

Data Structures and Algorithms · Computer Science 2021-08-11 Alexander Noe

We give several algorithms addressing computations of intersections of conjugate subgroups.

Group Theory · Mathematics 2018-11-13 Rita Gitik

In this paper, we present a comprehensive system for the treatment of the topic of limits--conceptually, computationally, and formally. The system addresses fundamental linguistic flaws in the standard presentation of limits, which attempts…

General Mathematics · Mathematics 2007-05-23 Frank Swenton

The Ramsey number $R(G_1,\dots,G_k)$ is the smallest $n$ such that every $k$-coloring of the edges of $K_n$ contains a monochromatic copy of $G_i$ in color $i$. Ramsey numbers are challenging to compute, and few are known exactly. We use…

Combinatorics · Mathematics 2025-09-05 William J. Wesley

The Ramsey number $r_k(p, q)$ is the smallest integer $N$ that satisfies for every red-blue coloring on $k$-subsets of $[N]$, there exist $p$ integers such that any $k$-subset of them is red, or $q$ integers such that any $k$-subset of them…

Combinatorics · Mathematics 2019-07-31 S. Cliff Liu

We study two related problems concerning the number of homogeneous subsets of given size in graphs that go back to questions of Erd\H{o}s. Most notably, we improve the upper bounds on the Ramsey multiplicity of $K_4$ and $K_5$ and settle…

Combinatorics · Mathematics 2024-09-16 Olaf Parczyk , Sebastian Pokutta , Christoph Spiegel , Tibor Szabó

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

We present quantum complexity lower and upper bounds for independent set problems in graphs. In particular, we give quantum algorithms for computing a maximal and a maximum independent set in a graph. We present applications of these…

Quantum Physics · Physics 2007-05-23 Sebastian Doern

An ordered graph $\mathcal{G}$ is a simple graph together with a total ordering on its vertices. The (2-color) Ramsey number of $\mathcal{G}$ is the smallest integer $N$ such that every 2-coloring of the edges of the complete ordered graph…

Combinatorics · Mathematics 2019-02-26 Jesse Geneson , Amber Holmes , Xujun Liu , Dana Neidinger , Yanitsa Pehova , Isaac Wass

Let $K\_{[k,t]}$ be the complete graph on $k$ vertices from which a set of edges, induced by a clique of order $t$, has been dropped. In this note we give two explicit upper bounds for $R(K\_{[k\_1,t\_1]},\dots, K\_{[k\_r,t\_r]})$ (the…

Combinatorics · Mathematics 2014-12-15 Jonathan Chappelon , Luis Pedro Montejano , Jorge Luis Ramírez Alfonsín

Topological mapping of a large physical system on a graph, and its decomposition using universal measures is proposed. We find inherent limits to the potential for optimization of a given system and its approximate representations by…

Social and Information Networks · Computer Science 2015-02-10 Vladan Mlinar

The prototypical high-dimensional statistics problem entails finding a structured signal in noise. Many of these problems exhibit an intriguing phenomenon: the amount of data needed by all known computationally efficient algorithms far…

Computational Complexity · Computer Science 2019-11-19 Matthew Brennan , Guy Bresler , Wasim Huleihel

For a partially ordered set $(A, \le)$, let $G_A$ be the simple, undirected graph with vertex set $A$ such that two vertices $a \neq b\in A$ are adjacent if either $a \le b$ or $b \le a$. We call $G_A$ the \emph{partial order graph} or…

Combinatorics · Mathematics 2020-10-22 Ayman Badawi , Roswitha Rissner

We establish new lower bounds for $28$ classical two and three color Ramsey numbers, and describe the heuristic search procedures we used. Several of the new three color bounds are derived from the two color constructions; specifically, we…

Combinatorics · Mathematics 2015-07-21 Geoffrey Exoo , Milos Tatarevic

This work is devoted to lower bounds on independence numbers of distance graphs with vertices in $\{-1,0,1\}^n$. The asymptotic case is studied, yielding new results over a broad range of parameters. Numerical results are presented,…

Combinatorics · Mathematics 2025-02-20 A. R. Akhiiarov , A. V. Bobu , A. M. Raigorodskii

We give an exponential lower bound for Berge-Ramsey problems.

Combinatorics · Mathematics 2020-01-23 Dömötör Pálvölgyi

We compute the number of circuits and of loops with multiple crossings in random regular graphs. We discuss the importance of this issue for the validity of the cavity approach. On the one side we obtain analytic results for the infinite…

Statistical Mechanics · Physics 2009-11-10 Enzo Marinari , Remi Monasson

Determining the crossing numbers of Cartesian products of small graphs with arbitrarily large paths has been an ongoing topic of research since the 1970s. Doing so requires the establishment of coincident upper and lower bounds; the former…

Combinatorics · Mathematics 2024-09-12 Zayed Asiri , Ryan Burdett , Markus Chimani , Michael Haythorpe , Alex Newcombe , Mirko H. Wagner

A numerical scheme for computing arc-length parametrized curves of low bending energy that are confined to convex domains is devised. The convergence of the discrete formulations to a continuous model and the unconditional stability of an…

Numerical Analysis · Mathematics 2022-03-18 Sören Bartels , Pascal Weyer
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