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Related papers: Dirac-type Theorems for Inhomogenous Random Graphs

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We study Hamiltonicity in graphs obtained as the union of a deterministic $n$-vertex graph $H$ with linear degrees and a $d$-dimensional random geometric graph $G^d(n,r)$, for any $d\geq1$. We obtain an asymptotically optimal bound on the…

Combinatorics · Mathematics 2022-09-29 Alberto Espuny Díaz

The study of graph discrepancy problems, initiated by Erd\H{o}s in the 1960s, has received renewed attention in recent years. In general, given a $2$-edge-coloured graph $G$, one is interested in embedding a copy of a graph $H$ in $G$ with…

Combinatorics · Mathematics 2024-06-28 Andrea Freschi , Allan Lo

Let $\{G_i\}$ be the random graph process: starting with an empty graph $G_0$ with $n$ vertices, in every step $i \geq 1$ the graph $G_i$ is formed by taking an edge chosen uniformly at random among the non-existing ones and adding it to…

Combinatorics · Mathematics 2018-08-31 Rajko Nenadov , Angelika Steger , Miloš Trujić

In this paper, the problem of matching pairs of correlated random graphs with multi-valued edge attributes is considered. Graph matching problems of this nature arise in several settings of practical interest including social network…

Information Theory · Computer Science 2018-02-06 F. Shirani , S. Garg , E. Erkip

The problem of graphical model selection is to correctly estimate the graph structure of a Markov random field given samples from the underlying distribution. We analyze the information-theoretic limitations of the problem of graph…

Information Theory · Computer Science 2009-05-19 Narayana Santhanam , Martin J. Wainwright

P\'osa's theorem states that any graph $G$ whose degree sequence $d_1 \le \ldots \le d_n$ satisfies $d_i \ge i+1$ for all $i < n/2$ has a Hamilton cycle. This degree condition is best possible. We show that a similar result holds for…

Combinatorics · Mathematics 2019-12-03 Padraig Condon , Alberto Espuny Díaz , Jaehoon Kim , Daniela Kühn , Deryk Osthus

In 1952, Dirac proved the following theorem about long cycles in graphs with large minimum vertex degrees: Every $n$-vertex $2$-connected graph $G$ with minimum vertex degree $\delta\geq 2$ contains a cycle with at least $\min\{2\delta,n\}$…

Data Structures and Algorithms · Computer Science 2024-04-15 Fedor V. Fomin , Petr A. Golovach , Danil Sagunov , Kirill Simonov

We investigate the asymptotic structure of a random perfect graph $P_n$ sampled uniformly from the perfect graphs on vertex set $\{1,\ldots,n\}$. Our approach is based on the result of Pr\"omel and Steger that almost all perfect graphs are…

Combinatorics · Mathematics 2017-09-07 Colin McDiarmid , Nikola Yolov

We introduce a new way to sample inhomogeneous random graphs designed to have a lot of flexibility in the assignment of the degree sequence and the individual edge probabilities while remaining tractable. To achieve this we run a Poisson…

Probability · Mathematics 2020-03-03 Lorenzo Federico

Given two distributions F and G on the nonnegative integers we propose an algorithm to construct in- and out-degree sequences from samples of i.i.d. observations from F and G, respectively, that with high probability will be graphical, that…

Probability · Mathematics 2012-07-12 Ningyuan Chen , Mariana Olvera-Cravioto

A tuple $(G_1,\dots,G_n)$ of graphs on the same vertex set of size $n$ is said to be Hamilton-universal if for every map $\chi: [n]\to[n]$ there exists a Hamilton cycle whose $i$-th edge comes from $G_{\chi(i)}$. Bowtell, Morris, Pehova and…

Combinatorics · Mathematics 2026-02-26 Micha Christoph , Anders Martinsson , Aleksa Milojević

The famous Dirac's Theorem gives an exact bound on the minimum degree of an $n$-vertex graph guaranteeing the existence of a hamiltonian cycle. We prove exact bounds of similar type for hamiltonian Berge cycles in $r$-uniform, $n$-vertex…

Combinatorics · Mathematics 2022-11-08 Alexandr Kostochka , Ruth Luo , Grace McCourt

Suppose $G$ is a $k$-uniform hypergraph on $n$ vertices such that every $(k-1)$-subset $S$ of $V(G)$ belongs to at least $\delta n$ edges, where $\delta> 1/2$. Let $\Psi(G)$ denote the number of tight Hamilton cycles in $G$, that is, cyclic…

Combinatorics · Mathematics 2026-04-17 Felix Joos , Xinyue Xie

We consider the problem of finding an edge in a hidden undirected graph $G = (V, E)$ with $n$ vertices, in a model where we only allowed queries that ask whether or not a subset of vertices contains an edge. We study the non-adaptive model…

Data Structures and Algorithms · Computer Science 2022-07-07 Ron Kupfer , Noam Nisan

The cycle space $\mathcal{C}(G)$ of a graph $G$ is defined as the linear space spanned by all cycles in $G$. For an integer $k\ge 3$, let $\mathcal{C}_k (G)$ denote the subspace of $\mathcal{C}(G)$ generated by the cycles of length exactly…

Combinatorics · Mathematics 2025-03-21 Xinmin Hou , Zhi Yin

In this paper we consider the existence of Hamilton cycles in the random graph $G=G_{n,m}^{\delta\geq 3}$. This a random graph chosen uniformly from the set of graphs with vertex set $[n]$, $m$ edges and minimum degree at least 3. Our…

Combinatorics · Mathematics 2020-06-23 Michael Anastos , Alan Frieze

A bipartite graph $H$ is said to have Sidorenko's property if the probability that the uniform random mapping from $V(H)$ to the vertex set of any graph $G$ is a homomorphism is at least the product over all edges in $H$ of the probability…

Combinatorics · Mathematics 2018-07-11 David Conlon , Jeong Han Kim , Choongbum Lee , Joonkyung Lee

In a random graph, counts for the number of vertices with given degrees will typically be dependent. We show via a multivariate normal and a Poisson process approximation that, for graphs which have independent edges, with a possibly…

Probability · Mathematics 2009-12-25 K. Lin , G. Reinert

Inhomogeneous random graphs are fundamental models for real-world networks, where prescribed degrees are imposed as soft constraints. A common assumption in such models is that the degree distribution follows a power-law, capturing the…

Probability · Mathematics 2026-03-09 Riccardo Michielan , Clara Stegehuis , Bert Zwart

We introduce a new setting of algorithmic problems in random graphs, studying the minimum number of queries one needs to ask about the adjacency between pairs of vertices of ${\mathcal G}(n,p)$ in order to typically find a subgraph…

Combinatorics · Mathematics 2016-08-05 Asaf Ferber , Michael Krivelevich , Benny Sudakov , Pedro Vieira