English
Related papers

Related papers: Loose paths in random ordered hypergraphs

200 papers

The size-Ramsey number $R^{(k)}(H)$ of a $k$-uniform hypergraph $H$ is the minimum number of edges in a $k$-uniform hypergraph $G$ with the property that every `$2$-edge coloring' of $G$ contains a monochromatic copy of $H$. For $k\ge2$ and…

Combinatorics · Mathematics 2022-06-22 Christian Winter

We show that w.h.p.\ the random $r$-uniform hypergraph $H_{n,m}$ contains a loose Hamilton cycle, provided $r\geq 3$ and $m\geq \frac{(1+\epsilon)n\log n}{r}$, where $\epsilon$ is an arbitrary positive constant. This is asymptotically best…

Combinatorics · Mathematics 2025-03-10 Alan Frieze , Xavier Perez-Gimenez

Consider a random regular graph with degree $d$ and of size $n$. Assign to each edge an i.i.d. exponential random variable with mean one. In this paper we establish a precise asymptotic expression for the maximum number of edges on the…

Probability · Mathematics 2012-10-10 Hamed Amini , Yuval Peres

A longest path in a graph is called a detour. It is easy to see that a connected graph of minimum degree at least $2$ and order at least $4$ has at least $4$ detours. We prove that if the number of detours in such a graph of order at least…

Combinatorics · Mathematics 2023-12-05 Xingzhi Zhan

An ordered graph is a graph with a linear ordering on its vertices. The online Ramsey game for ordered graphs $G$ and $H$ is played on an infinite sequence of vertices; on each turn, Builder draws an edge between two vertices, and Painter…

Combinatorics · Mathematics 2024-03-29 Felix Christian Clemen , Emily Heath , Mikhail Lavrov

Paths are important structural elements in complex networks because they are finite (unlike walks), related to effective node coverage (minimum spanning trees), and can be understood as being dual to star connectivity. This article…

Physics and Society · Physics 2007-12-05 Luciano da Fontoura Costa

We present an all-pairs shortest path algorithm whose running time on a complete directed graph on $n$ vertices whose edge weights are chosen independently and uniformly at random from $[0,1]$ is $O(n^2)$, in expectation and with high…

Combinatorics · Mathematics 2011-05-20 Yuval Peres , Dimitry Sotnikov , Benny Sudakov , Uri Zwick

Computing a shortest path between two nodes in an undirected unweighted graph is among the most basic algorithmic tasks. Breadth first search solves this problem in linear time, which is clearly also a lower bound in the worst case.…

Data Structures and Algorithms · Computer Science 2023-08-01 Noga Alon , Allan Grønlund , Søren Fuglede Jørgensen , Kasper Green Larsen

We consider a constrained version of the shortest path problem on the complete graphs whose edges have independent random lengths and costs. We establish the asymptotic value of the minimum length as a function of the cost-budget within a…

Combinatorics · Mathematics 2021-11-16 Alan Frieze , Tomasz Tkocz

We study the emergence of loose Hamilton cycles in subgraphs of random hypergraphs. Our main result states that the minimum $d$-degree threshold for loose Hamiltonicity relative to the random $k$-uniform hypergraph $H_k(n,p)$ coincides with…

Combinatorics · Mathematics 2023-09-26 José D. Alvarado , Yoshiharu Kohayakawa , Richard Lang , Guilherme O. Mota , Henrique Stagni

We consider the following definition of connectivity in $k$-uniform hypergraphs: Two $j$-sets are $j$-connected if there is a walk of edges between them such that two consecutive edges intersect in at least $j$ vertices. We determine the…

Combinatorics · Mathematics 2015-02-26 Oliver Cooley , Mihyun Kang , Christoph Koch

The $s$-colour size-Ramsey number of a hypergraph $H$ is the minimum number of edges in a hypergraph $G$ whose every $s$-edge-colouring contains a monochromatic copy of $H$. We show that the $s$-colour size-Ramsey number of the $r$-uniform…

Combinatorics · Mathematics 2025-07-03 Shoham Letzter , Alexey Pokrovskiy , Liana Yepremyan

Let $G=(V,E,w)$ be a weighted directed graph without negative cycles. For two vertices $s,t\in V$, we let $d_{\le h}(s,t)$ be the minimum, according to the weight function $w$, of a path from $s$ to $t$ that uses at most $h$ edges, or hops.…

Data Structures and Algorithms · Computer Science 2024-11-01 Virginia Vassilevska Williams , Zoe Xi , Yinzhan Xu , Uri Zwick

We study a variant of the Erd\H{o}s Matching Problem in random hypergraphs. Let $\mathcal{K}_p(n,k)$ denote the Erd\H{o}s-R\'enyi random $k$-uniform hypergraph on $n$ vertices where each possible edge is included with probability $p$. We…

Combinatorics · Mathematics 2025-09-24 Peter Frankl , Jiaxi Nie , Jian Wang

We say that a $k$-uniform hypergraph $C$ is a Hamilton cycle of type $\ell$, for some $1\le \ell \le k$, if there exists a cyclic ordering of the vertices of $C$ such that every edge consists of $k$ consecutive vertices and for every pair…

Combinatorics · Mathematics 2010-03-10 Alan Frieze , Michael Krivelevich

Let $H_d(n,p)$ signify a random $d$-uniform hypergraph with $n$ vertices in which each of the ${n}\choose{d}$ possible edges is present with probability $p=p(n)$ independently, and let $H_d(n,m)$ denote a uniformly distributed with $n$…

Combinatorics · Mathematics 2014-06-27 Michael Behrisch , Amin Coja-Oghlan , Mihyun Kang

Let $f(n,H)$ denote the maximum number of copies of $H$ in an $n$-vertex planar graph. The order of magnitude of $f(n,P_k)$, where $P_k$ is a path on $k$ vertices, is $n^{{\lfloor{\frac{k-1}{2}}\rfloor}+1}$. In this paper we determine the…

Combinatorics · Mathematics 2021-10-18 Debarun Ghosh , Ervin Győri , Ryan R. Martin , Addisu Paulos , Nika Salia , Chuanqi Xiao , Oscar Zamora

An ordered hypergraph is a hypergraph $G$ whose vertex set $V(G)$ is linearly ordered. We find the Tur\'an numbers for the $r$-uniform $s$-vertex tight path $P^{(r)}_s$ (with vertices in the natural order) exactly when $r\le s < 2r$ and $n$…

Combinatorics · Mathematics 2022-12-29 John P. Bright , Kevin G. Milans , Jackson Porter

We make progress toward a characterization of the graphs $H$ such that every connected $H$-free graph has a longest path transversal of size $1$. In particular, we show that the graphs $H$ on at most $4$ vertices satisfying this property…

Combinatorics · Mathematics 2025-04-23 James A. Long , Kevin G. Milans , Andrea Munaro

Optimal paths connecting randomly selected network nodes and fixed routers are studied analytically in the presence of non-linear overlap cost that penalizes congestion. Routing becomes increasingly more difficult as the number of selected…

Disordered Systems and Neural Networks · Physics 2012-05-15 Chi Ho Yeung , David Saad