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Related papers: Tight paths in convex geometric hypergraphs

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A graph $H$ is \emph{common} if the number of monochromatic copies of $H$ in a 2-edge-colouring of the complete graph $K_n$ is asymptotically minimised by the random colouring, or equivalently, $t_H(W)+t_H(1-W)\geq 2^{1-e(H)}$ holds for…

Combinatorics · Mathematics 2022-10-04 Jang Soo Kim , Joonkyung Lee

By a tight tour in a $k$-uniform hypergraph $H$ we mean any sequence of its vertices $(w_0,w_1,\ldots,w_{s-1})$ such that for all $i=0,\ldots,s-1$ the set $e_i=\{w_i,w_{i+1}\ldots,w_{i+k-1}\}$ is an edge of $H$ (where operations on indices…

Computational Complexity · Computer Science 2023-06-22 Zbigniew Lonc , Paweł Naroski , Paweł Rzążewski

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

One of the central topics in extremal graph theory is the study of the function $ex(n,H)$, which represents the maximum number of edges a graph with $n$ vertices can have while avoiding a fixed graph $H$ as a subgraph. Tur{\'a}n provided a…

History and Overview · Mathematics 2025-03-18 Shakhar Smorodinsky

We prove that any bounded degree regular graph with sufficiently strong spectral expansion contains an induced path of linear length. This is the first such result for expanders, strengthening an analogous result in the random setting by…

Combinatorics · Mathematics 2025-03-05 Nemanja Draganić , Peter Keevash

We prove Farber's conjecture on the stable topological complexity of configuration spaces of graphs. The conjecture follows from a general lower bound derived from recent insights into the topological complexity of aspherical spaces. Our…

Algebraic Topology · Mathematics 2022-09-20 Ben Knudsen

We state the graph-theoretic computational problem of finding tight paths in a directed, edge-weighted graph, as well as its simplification of finding tight pairs. These problems are motivated by the need of algorithms that find so-called…

Data Structures and Algorithms · Computer Science 2025-06-12 José Luis Balcázar

We consider the problem of partitioning the edges of a graph into as few paths as possible. This is a~subject of the classic conjecture of Gallai and a recurring topic in combinatorics. Regarding the complexity of partitioning a graph…

Data Structures and Algorithms · Computer Science 2026-02-16 Tomáš Masařík , Michał Włodarczyk , Mehmet Akif Yıldız

We give the first exact and stability results for a hypergraph Tur\'{a}n problem with infinitely many extremal constructions that are far from each other in edit-distance. This includes an example of triple systems with Tur\'{a}n density…

Combinatorics · Mathematics 2023-12-04 Jianfeng Hou , Heng Li , Xizhi Liu , Dhruv Mubayi , Yixiao Zhang

We prove that for any weakly convergent sequence of finite graphs with bounded vertex degrees, there exists a topological limit graphing.

Combinatorics · Mathematics 2007-05-23 Gabor Elek

We derive various inequalities involving the intersection number of the curves contained in geodesics and tight geodesics in the curve graph. While there already exist such inequalities on tight geodesics, our method applies in the setting…

Geometric Topology · Mathematics 2016-03-14 Yohsuke Watanabe

We consider the Erd\H{o}s-R\'enyi evolution of random graphs, where a new uniformly distributed edge is added to the graph in every step. For every fixed $d\ge 1$, we show that with high probability, the graph becomes rigid in $\mathbb R^d$…

Combinatorics · Mathematics 2022-09-14 Alan Lew , Eran Nevo , Yuval Peled , Orit E. Raz

Generalized Tur\'an problems have been a central topic of study in extremal combinatorics throughout the last few decades. One such problem is maximizing the number of cliques of size $t$ in a graph of a fixed order that does not contain…

Combinatorics · Mathematics 2024-03-01 Debsoumya Chakraborti , Da Qi Chen

In the 1980s, Erd\H{o}s and S\'os initiated the study of Tur\'an problems with a uniformity condition on the distribution of edges: the uniform Tur\'an density of a hypergraph $H$ is the infimum over all $d$ for which any sufficiently large…

Combinatorics · Mathematics 2026-02-25 Frederik Garbe , Daniel Iľkovič , Daniel Kráľ , Filip Kučerák , Ander Lamaison

This paper provides an overview of results, concerning longest or heaviest paths, in the area of random directed graphs on the integers along with some extensions. We study first-order asymptotics of heaviest paths allowing weights both on…

Probability · Mathematics 2018-08-09 Sergey Foss , Takis Konstantopoulos

We develop a quantitative large deviations theory for random hypergraphs, which rests on tensor decomposition and counting lemmas under a novel family of cut-type norms. As our main application, we obtain sharp asymptotics for joint upper…

Probability · Mathematics 2023-05-10 Nicholas A. Cook , Amir Dembo , Huy Tuan Pham

We give an algorithmic proof for the existence of tight Hamilton cycles in a random r-uniform hypergraph with edge probability p=n^{-1+eps} for every eps>0. This partly answers a question of Dudek and Frieze [Random Structures Algorithms],…

Combinatorics · Mathematics 2013-01-25 Peter Allen , Julia Böttcher , Yoshiharu Kohayakawa , Yury Person

An extremal graph for a given graph $H$ is a graph with maximum number of edges on fixed number of vertices without containing a copy of $H$. The $k$-th power of a path is a graph obtained from a path and joining all pair of vertices of the…

Combinatorics · Mathematics 2020-03-31 Long-Tu Yuan

For two graphs $F$ and $H$, the relative Tur\'{a}n number $\mathrm{ex}(H,F)$ is the maximum number of edges in an $F$-free subgraph of $H$. Foucaud, Krivelevich, and Perarnau \cite{FKP} and Perarnau and Reed \cite{PR} studied these…

Combinatorics · Mathematics 2021-06-18 Sam Spiro , Jacques Verstraëte

The Tur\'{a}n number of a graph $H$ is the maximum number of edges in any graph of order $n$ that does not contain $H$ as a subgraph. In 1959, Erd\H os and Gallai obtained a sharp upper bound of Tur\'{a}n numbers for a path of arbitrary…

Combinatorics · Mathematics 2025-11-04 Miao Dong , Bo Ning , Long-Tu Yuan , Xiao-Dong Zhang