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We give a generalization to a continuous setting of the classic Markov chain tree Theorem. In particular, we consider an irreducible diffusion process on a metric graph. The unique invariant measure has an atomic component on the vertices…

Probability · Mathematics 2020-02-04 Michele Aleandri , Matteo Colangeli , Davide Gabrielli

Suppose that the vertices of a graph $G$ are colored with two colors in an unknown way. The color that occurs on more than half of the vertices is called the majority color (if it exists), and any vertex of this color is called a majority…

We study the typical structure and the number of triangle-free graphs with $n$ vertices and $m$ edges where $m$ is large enough so that a typical triangle-free graph has a cut containing nearly all of its edges, but may not be bipartite.…

Combinatorics · Mathematics 2025-08-14 Matthew Jenssen , Will Perkins , Aditya Potukuchi

We derive an asymptotic formula for the number of strongly connected digraphs with $n$ vertices and $m$ arcs (directed edges), valid for $m-n\to\infty$ as $n\to \infty$ provided $m=O(n\log n)$. This fills the gap between Wright's results…

Combinatorics · Mathematics 2011-05-18 Xavier Perez-Gimenez , Nicholas Wormald

We show that the profile of the tree constructed by the Depth First Search Algorithm in the giant component of an Erd\H{o}s-R\'enyi graph with $N$ vertices and connection probability $c/N$ converges to an explicit deterministic shape. This…

Probability · Mathematics 2020-03-16 Nathanaël Enriquez , Gabriel Faraud , Laurent Ménard

Many well-known problems in Combinatorics can be reduced to finding a large rainbow structure in a certain edge-coloured multigraph. Two celebrated examples of this are Ringel's tree packing conjecture and Ryser's conjecture on transversals…

Combinatorics · Mathematics 2021-10-05 David Munhá Correia , Benny Sudakov

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

Broadcasting in a computer network is a method of transferring a message to all recipients simultaneously. It is common in this situation to use a tree with many leaves to perform the broadcast, as internal nodes have to forward the…

Data Structures and Algorithms · Computer Science 2020-07-16 Cristina G. Fernandes , Carla N. Lintzmayer

We consider a graph coloring algorithm that processes vertices in order taken uniformly at random and assigns colors to them using First-Fit strategy. We show that this algorithm uses, in expectation, at most $(1 + o(1))\cdot \ln n \,/\,…

Discrete Mathematics · Computer Science 2024-08-09 Bartłomiej Bosek , Grzegorz Gutowski , Michał Lasoń , Jakub Przybyło

The broadcasting models on a d-ary tree T arise in many contexts such as biology, information theory, statistical physics and computer science. We consider the k-colouring model, i.e. the root of T is assigned an arbitrary colour and,…

Discrete Mathematics · Computer Science 2013-11-08 Charilaos Efthymiou

When $k|n$, the tree $\mathrm{Comb}_{n,k}$ consists of a path containing $n/k$ vertices, each of whose vertices has a disjoint path length $k-1$ beginning at it. We show that, for any $k=k(n)$ and $\epsilon>0$, the binomial random graph…

Combinatorics · Mathematics 2014-05-27 Richard Montgomery

We consider a discrete-time dynamical process on graphs, firstly introduced in connection with a protocol for controlling large networks of spin 1/2 quantum mechanical particles [Phys. Rev. Lett. 99, 100501 (2007)]. A description is as…

Combinatorics · Mathematics 2013-09-17 Simone Severini

Accessibility percolation is a new type of percolation problem inspired by evolutionary biology. To each vertex of a graph a random number is assigned and a path through the graph is called accessible if all numbers along the path are in…

Statistical Mechanics · Physics 2013-04-04 Stefan Nowak , Joachim Krug

As a generalization of the Edmonds arborescence packing theorem, Kamiyama--Katoh--Takizawa (2009) gave a good characterization of directed graphs that contain arc-disjoint arborescences spanning the set of vertices reachable from each root.…

Discrete Mathematics · Computer Science 2018-08-23 Tatsuya Matsuoka , Shin-ichi Tanigawa

We prove that, with high probability, in every $2$-edge-colouring of the random tournament on $n$ vertices there is a monochromatic copy of every oriented tree of order $O (n / \sqrt{\log n})$. This generalises a result of the first, third…

Combinatorics · Mathematics 2020-06-03 Matija Bucic , Sven Heberle , Shoham Letzter , Benny Sudakov

An antimagic labeling of a digraph $D$ with $n$ vertices and $m$ arcs is a bijection from the set of arcs of $D$ to $\{1,2,\cdots,m\}$ such that all $n$ oriented vertex-sums are pairwise distinct, where the oriented vertex-sum of a vertex…

Combinatorics · Mathematics 2021-11-09 Songling Shan , Xiaowei Yu

Let $G$ be a connected multigraph with $n$ vertices, and suppose $G$ has been edge-colored with $n-1$ colors so that each color class induces a spanning tree. Rota's Basis Conjecture for graphic matroids posits that one can find $n-1$…

Combinatorics · Mathematics 2023-11-02 Anant Asthana , Shreev Goyal

In this paper we show how to use simple partitioning lemmas in order to embed spanning graphs in a typical member of $G(n,p)$. Let the \emph{maximum density} of a graph $H$ be the maximum average degree of all the subgraphs of $H$. First,…

Combinatorics · Mathematics 2014-09-23 Asaf Ferber , Rajko Nenadov , Ueli Peter

We study the problem of sampling a uniformly random directed rooted spanning tree, also known as an arborescence, from a possibly weighted directed graph. Classically, this problem has long been known to be polynomial-time solvable; the…

Data Structures and Algorithms · Computer Science 2020-12-18 Nima Anari , Nathan Hu , Amin Saberi , Aaron Schild

In this paper we study the randomly edge colored graph that is obtained by adding randomly colored random edges to an arbitrary randomly edge colored dense graph. In particular we ask how many colors and how many random edges are needed so…

Combinatorics · Mathematics 2018-02-02 Michael Anastos , Alan Frieze