English
Related papers

Related papers: Leaf-to-leaf paths of many lengths

200 papers

A classical result of Koml\'os, S\'ark\"ozy and Szemer\'edi shows that every large $n$-vertex graph with minimum degree at least $(1/2+\gamma)n$ contains all spanning trees of bounded degree. We generalised this result to loose spanning…

Combinatorics · Mathematics 2025-02-10 Yaobin Chen , Allan Lo

Inspired by the spread of information in social networks and graph-theoretic processes such as Firefighting and graph cleaning, Bonato, Janssen and Roshanbin introduced in 2016 the burning number $b(G)$ of any finite graph $G$. They…

Combinatorics · Mathematics 2025-09-08 Jiajun Ning , Xian'an Jin , Meiqiao Zhang

A famous conjecture of Erd\H{o}s and S\'os states that every graph with average degree more than $k - 1$ contains all trees with $k$ edges as subgraphs. We prove that the Erd\H{o}s-S\'os conjecture holds approximately, if the size of the…

Combinatorics · Mathematics 2018-10-30 Václav Rozhoň

Klimo\v{s}ov\'a, Piguet, and Rozho\v{n} conjectured that any graph with minimum degree $k/2$ and sufficiently many vertices of degree $k$ should contain all trees with $k$ edges. We prove an asymptotic version of this conjecture for dense…

Combinatorics · Mathematics 2026-03-19 Akbar Davoodi , Diana Piguet , Hanka Řada , Nicolás Sanhueza-Matamala

We study the average leaf-to-leaf path lengths on ordered Catalan tree graphs with $n$ nodes and show that these are equivalent to the average length of paths starting from the root node. We give an explicit analytic formula for the average…

In new progress on conjectures of Stein, and Addario-Berry, Havet, Linhares Sales, Reed and Thomass\'e, we prove that every oriented graph with all in- and out-degrees greater than 5k/8 contains an alternating path of length k. This…

Combinatorics · Mathematics 2025-09-08 Jozef Skokan , Mykhaylo Tyomkyn

The Pathwidth Theorem states that if a class of graphs has unbounded pathwidth, then it contains all trees as graph minors. We prove a similar result for dense graphs. More precisely, we give a finite family of tree-like patterns and prove…

Logic in Computer Science · Computer Science 2026-04-09 Mikołaj Bojańczyk , Pierre Ohlmann

A "tree-partition" of a graph $G$ is a partition of $V(G)$ such that identifying the vertices in each part gives a tree. It is known that every graph with treewidth $k$ and maximum degree $\Delta$ has a tree-partition with parts of size…

Combinatorics · Mathematics 2023-07-31 Marc Distel , David R. Wood

Given points in Euclidean space of arbitrary dimension, we prove that there exists a spanning tree having no vertices of degree greater than 3 with weight at most 1.559 times the weight of the minimum spanning tree. We also prove that there…

Computational Geometry · Computer Science 2014-07-18 Samuel Zbarsky

Loebl, Koml\'os and S\'os conjectured that every $n$-vertex graph $G$ with at least $n/2$ vertices of degree at least $k$ contains each tree $T$ of order $k+1$ as a subgraph. We give a sketch of a proof of the approximate version of this…

Combinatorics · Mathematics 2017-07-31 Jan Hladky , Diana Piguet , Miklos Simonovits , Maya Stein , Endre Szemeredi

The linear arboricity la(G) of a graph G is the minimum number of linear forests that partition the edges of G. In 1984, Akiyama et al. stated the Linear Arboricity Conjecture (LAC), that the linear arboricity of any simple graph of maximum…

Combinatorics · Mathematics 2012-09-06 Marek Cygan , Lukasz Kowalik , Borut Luzar

We show that the edges of any planar graph of maximum degree at most $9$ can be partitioned into $4$ linear forests and a matching. Combined with known results, this implies that the edges of any planar graph $G$ of odd maximum degree…

Combinatorics · Mathematics 2023-02-28 Marthe Bonamy , Jadwiga Czyżewska , Łukasz Kowalik , Michał Pilipczuk

We prove that if a graph has a tree-decomposition of width at most w, then it has a tree-decomposition of width at most w with certain desirable properties. We will use this result in a subsequent paper to show that every 2-connected graph…

Combinatorics · Mathematics 2018-04-17 Thanh N. Dang , Robin Thomas

For an undirected tree with $n$ edges labelled by single letters, we consider its substrings, which are labels of the simple paths between pairs of nodes. We prove that there are $O(n^{1.5})$ different palindromic substrings. This solves an…

Data Structures and Algorithms · Computer Science 2020-11-30 Paweł Gawrychowski , Tomasz Kociumaka , Wojciech Rytter , Tomasz Waleń

Leaves, i.e., vertices of degree one, can play a significant role in graph structure, especially in sparsely connected settings in which leaves often constitute the largest fraction of vertices. We consider a leaf-based counterpart of the…

Statistical Mechanics · Physics 2025-11-07 Harrison Hartle , P. L. Krapivsky

The Linear Arboricity Conjecture asserts that the linear arboricity of a graph with maximum degree $\Delta$ is $\lceil (\Delta+1)/2 \rceil$. For a $2k$-regular graph $G$, this implies $la(G) = k+1$. In this note, we utilize a network flow…

Combinatorics · Mathematics 2025-12-15 Tapas Kumar Mishra

Ply number is a recently developed graph drawing metric inspired by studying road networks. Informally, for each vertex v, which is associated with a point in the plane, a disk is drawn centered on v with a radius that is alpha times the…

Computational Geometry · Computer Science 2018-08-13 Michael T. Goodrich , Timothy Johnson

We investigate the structure of trees that have minimal algebraic connectivity among all trees with a given degree sequence. We show that such trees are caterpillars and that the vertex degrees are non-decreasing on every path on…

Combinatorics · Mathematics 2008-10-07 Tuerker Biyikoglu , Josef Leydold

Trees without vertices of degree $2$ are sometimes named topological trees. In this work, we bring forward the study of the inducibility of (rooted) topological trees with a given number of leaves. The inducibility of a topological tree $S$…

Combinatorics · Mathematics 2018-02-20 Audace Amen Vioutou Dossou-Olory , Stephan Wagner

We ask the question, which oriented trees $T$ must be contained as subgraphs in every finite directed graph of sufficiently large minimum out-degree. We formulate the following simple condition: all vertices in $T$ of in-degree at least $2$…