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Related papers: Random perturbation of sparse graphs

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For a given $\delta \in (0,1)$, the randomly perturbed graph model is defined as the union of any $n$-vertex graph $G_0$ with minimum degree $\delta n$ and the binomial random graph $\mathbf{G}(n,p)$ on the same vertex set. Moreover, we say…

Combinatorics · Mathematics 2025-11-10 Kyriakos Katsamaktsis , Shoham Letzter , Amedeo Sgueglia

We study conditions under which a given hypergraph is randomly robust Hamiltonian, which means that a random sparsification of the host graph contains a Hamilton cycle with high probability. Our main contribution provides nearly optimal…

Combinatorics · Mathematics 2024-12-31 Felix Joos , Richard Lang , Nicolás Sanhueza-Matamala

A graph is Hamiltonian if it contains a cycle which passes through every vertex of the graph exactly once. A classical theorem of Dirac from 1952 asserts that every graph on $n$ vertices with minimum degree at least $n/2$ is Hamiltonian. We…

Combinatorics · Mathematics 2012-09-24 Michael Krivelevich , Choongbum Lee , Benny Sudakov

A perfect $H$-tiling in a graph $G$ is a collection of vertex-disjoint copies of a graph $H$ in $G$ that together cover all the vertices in $G$. In this paper we investigate perfect $H$-tilings in a random graph model introduced by Bohman,…

Combinatorics · Mathematics 2018-05-14 József Balogh , Andrew Treglown , Adam Zsolt Wagner

We introduce a natural generalization of the Erd\H{o}s-R\'enyi random graph model in which random instances of a fixed motif are added independently. The binomial random motif graph $G(H,n,p)$ is the random (multi)graph obtained by adding…

Combinatorics · Mathematics 2019-07-30 Michael Anastos , Peleg Michaeli , Samantha Petti

We investigate the threshold probability for connectivity of sparse graphs under weak assumptions. As a corollary this completely solve the problem for Cartesian powers of arbitrary graphs. In detail, let $G$ be a connected graph on $k$…

Combinatorics · Mathematics 2013-12-04 Felix Joos

A class of graphs is bridge-addable if given a graph $G$ in the class, any graph obtained by adding an edge between two connected components of $G$ is also in the class. The authors recently proved a conjecture of McDiarmid, Steger, and…

Combinatorics · Mathematics 2021-09-06 Guillaume Chapuy , Guillem Perarnau

A random algebraic graph is defined by a group $G$ with a uniform distribution over it and a connection $\sigma:G\longrightarrow[0,1]$ with expectation $p,$ satisfying $\sigma(g)=\sigma(g^{-1}).$ The random graph…

Probability · Mathematics 2023-05-10 Kiril Bangachev , Guy Bresler

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

The renowned theorem of Dirac states that if $G$ is a graph with minimum degree at least $n/2$ then $G$ has a Hamilton cycle. A natural generalisation asks what properties of an edge-colouring of $G$ guarantee the existence of a properly…

Combinatorics · Mathematics 2026-03-24 Natalie Behague , Francesco Di Braccio , Bertille Granet , Allan Lo

Let $X_1,..., X_n$ be independent, uniformly random points from $[0,1]^2$. We prove that if we add edges between these points one by one by order of increasing edge length then, with probability tending to 1 as the number of points $n$…

Combinatorics · Mathematics 2009-06-15 Michael Krivelevich , Tobias Muller

The classical Dirac theorem asserts that every graph $G$ on $n$ vertices with minimum degree $\delta(G) \ge \lceil n/2 \rceil$ is Hamiltonian. The lower bound of $\lceil n/2 \rceil$ on the minimum degree of a graph is tight. In this paper,…

Discrete Mathematics · Computer Science 2016-06-14 Yasemin Büyükçolak , Didem Gözüpek , Sibel Özkan , Mordechai Shalom

Chen, Faudree, Gould, Jacobson, and Lesniak determined the minimum degree threshold for which a balanced $k$-partite graph has a Hamiltonian cycle. We give an asymptotically tight minimum degree condition for Hamiltonian cycles in arbitrary…

Combinatorics · Mathematics 2019-10-10 Louis DeBiasio , Robert A. Krueger , Dan Pritikin , Eli Thompson

What minimum degree of a graph $G$ on $n$ vertices guarantees that the union of $G$ and a random $2$-factor (or permutation) is with high probability Hamiltonian? Gir\~ao and Espuny D{\'\i}az showed that the answer lies in the interval…

Combinatorics · Mathematics 2025-02-04 Nemanja Draganić , Peter Keevash

For a graph $G$ the random $n$-lift of $G$ is obtained by replacing each of its vertices by a set of $n$ vertices, and joining a pair of sets by a random matching whenever the corresponding vertices of $G$ are adjacent. We show that…

Combinatorics · Mathematics 2014-01-07 Tomasz Łuczak , Łukasz Witkowski , Marcin Witkowski

A famous result by R\"odl, Ruci\'nski, and Szemer\'edi guarantees a (tight) Hamilton cycle in $k$-uniform hypergraphs $H$ on $n$ vertices with minimum $(k-1)$-degree $\delta_{k-1}(H)\geq (1/2+o(1))n$, thereby extending Dirac's result from…

Combinatorics · Mathematics 2021-04-14 Felix Joos , Marcus Kühn , Bjarne Schülke

Let $\mathcal{G}(n,r,s)$ denote a uniformly random $r$-regular $s$-uniform hypergraph on $n$ vertices, where $s$ is a fixed constant and $r=r(n)$ may grow with $n$. An $\ell$-overlapping Hamilton cycle is a Hamilton cycle in which…

Combinatorics · Mathematics 2019-11-04 Daniel Altman , Catherine Greenhill , Mikhail Isaev , Reshma Ramadurai

We present fast and efficient randomized distributed algorithms to find Hamiltonian cycles in random graphs. In particular, we present a randomized distributed algorithm for the $G(n,p)$ random graph model, with number of nodes $n$ and…

Data Structures and Algorithms · Computer Science 2018-04-25 Soumyottam Chatterjee , Reza Fathi , Gopal Pandurangan , Nguyen Dinh Pham

We investigate first passage percolation on inhomogeneous random graphs. The random graph model G(n,kappa) we study is the model introduced by Bollob\'as, Janson and Riordan, where each vertex has a type from a type space S and edge…

Probability · Mathematics 2016-11-14 István Kolossváry , Júlia Komjáthy

For integers $k \geq 3$ and $r\geq 2$, we show that for every $\alpha> 0$, there exists $\varepsilon > 0$ such that the union of $k$-uniform hypergraph on $n$ vertices with minimum codegree at least $\alpha n$ and a binomial random…

Combinatorics · Mathematics 2022-11-07 Yulin Chang , Jie Han , Lubos Thoma
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