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Using uniformization, Cantor type sets can be regarded as boundaries of rooted trees. In this setting, we show that the trace of a first-order Sobolev space on the boundary of a regular rooted tree is exactly a Besov space with an explicit…

Functional Analysis · Mathematics 2017-05-08 Anders Björn , Jana Björn , James T. Gill , Nageswari Shanmugalingam

A graph is called integral if all eigenvalues of its adjacency matrix consist entirely of integers. Recently, Csikvari proved the existence of integral trees of any even diameter. In the odd case, integral trees have been constructed with…

Combinatorics · Mathematics 2010-11-23 E. Ghorbani , A. Mohammadian , B. Tayfeh-Rezaie

We study a notion of potential isomorphism, where two structures are said to be potentially isomorphic if they are isomorphic in some generic extension that preserves stationary sets and does not add new sets of cardinality less than the…

Logic · Mathematics 2007-05-23 Alex Hellsten , Tapani Hyttinen , Saharon Shelah

We study the construction of quasimorphisms on groups acting on trees introduced by Monod and Shalom, that we call median quasimorphisms, and in particular we fully characterise actions on trees that give rise to non-trivial median…

Group Theory · Mathematics 2014-12-01 Alessandra Iozzi , Cristina Pagliantini , Alessandro Sisto

We prove that every oriented tree on $n$ vertices with bounded maximum degree appears as a spanning subdigraph of every directed graph on $n$ vertices with minimum semidegree at least $n/2+o(n)$. This can be seen as a directed graph…

Combinatorics · Mathematics 2026-05-20 Richard Mycroft , Tássio Naia

In this paper we show that all infinite trees which have bounded coordination and whose surface is negligible with respect to the volume in the limit of large distances (so that they can be embedded in a finite-dimensional euclidean space)…

Condensed Matter · Physics 2007-05-23 L. Donetti

We prove that, if $m$ is sufficiently large, every graph on $m+1$ vertices that has a universal vertex and minimum degree at least $\lfloor \frac{2m}{3} \rfloor$ contains each tree $T$ with $m$ edges as a subgraph. Our result confirms, for…

Combinatorics · Mathematics 2022-07-21 Bruce Reed , Maya Stein

We investigate the connections between tree amalgamations and quasi-isometries. In particular, we prove that the quasi-isometry type of multi-ended accessible quasi-transitive connected locally finite graphs is determined by the…

Combinatorics · Mathematics 2018-12-13 Matthias Hamann

We establish uniformization results for metric spaces that are homeomorphic to the euclidean plane or sphere and have locally finite Hausdorff 2-measure. Applying the geometric definition of quasiconformality, we give a necessary and…

Complex Variables · Mathematics 2016-08-29 Kai Rajala

Let $\mathcal{T}_n$ be the set of trees with $n$ vertices. Suppose that each tree in $\mathcal{T}_n$ is equally likely. We show that the number of different rooted trees of a tree equals $(\mu_r+o(1))n$ for almost every tree of…

Combinatorics · Mathematics 2013-05-21 Xueliang Li , Yiyang Li , Yongtang Shi

The cellular tree classifier model addresses a fundamental problem in the design of classifiers for a parallel or distributed computing world: Given a data set, is it sufficient to apply a majority rule for classification, or shall one…

Machine Learning · Statistics 2013-06-26 Gérard Biau , Luc Devroye

We consider the rooted trees which not have isomorphic representation and introduce a conception of complexity a natural number also. The connection between quantity such trees with $n$ edges and a complexity of natural number $n$ is…

Combinatorics · Mathematics 2012-05-03 B. S. Kochkarev

A perfect forest is a spanning forest of a connected graph $G$, all of whose components are induced subgraphs of $G$ and such that all vertices have odd degree in the forest. A perfect forest generalised a perfect matching since, in a…

Combinatorics · Mathematics 2016-12-16 Yair Caro , Josef Lauri , Christina Zarb

The relationship between two important problems in tree pattern matching, the largest common subtree and the smallest common supertree problems, is established by means of simple constructions, which allow one to obtain a largest common…

Data Structures and Algorithms · Computer Science 2007-05-23 Francesc Rossello , Gabriel Valiente

We construct a quasiconformal mapping of $n$-dimensional Euclidean space, $n \geq 2$, that simultaneously distorts the Hausdorff dimension of a nearly maximal collection of parallel lines by a given amount. This answers a question of…

Metric Geometry · Mathematics 2016-01-28 Zoltán M. Balogh , Jeremy T. Tyson , Kevin Wildrick

In this paper and a companion paper, we prove that, if $m$ is sufficiently large, every graph on $m+1$ vertices that has a universal vertex and minimum degree at least $\lfloor \frac{2m}{3} \rfloor$ contains each tree $T$ with $m$ edges as…

Combinatorics · Mathematics 2022-07-21 Bruce Reed , Maya Stein

A partial order is universal if it contains every countable partial order as a suborder. In 2017, Fiala, Hubi\v{c}ka, Long and Ne\v{s}et\v{r}il showed that every interval in the homomorphism order of graphs is universal, with the only…

Combinatorics · Mathematics 2022-01-26 Jan Hubička , Jaroslav Nešetřil , Pablo Oviedo , Oriol Serra

We give exact values and bounds on the isoperimetric peak of complete trees, improving on known results. For the complete $q$-ary tree of depth $d$, if $q\ge 5$, then we find that the isoperimetric peak equals $d$, completing an open…

Combinatorics · Mathematics 2025-11-11 Anthony Bonato , Lazar Mandic , Trent G. Marbach , Matthew Ritchie

A partial order is called semilinear iff the upper bounds of each element are linearly ordered and any two elements have a common upper bound. There exists, up to isomorphism, a unique countable existentially closed semilinear order, which…

A BC-tree (block-cutpoint-tree) is a tree (with at least two vertices) where the distance between any two leaves is even. Motivated from the study of the "core" of a graph, BC-trees provide an interesting class of trees. We consider…

Discrete Mathematics · Computer Science 2013-05-22 Yu Yang , Deqiang Wang , Hua Wang , Hongbo Liu