English
Related papers

Related papers: Spanning trees and continued fractions

200 papers

We conjecture that the distribution of the edge-disjoint union of two random regular graphs on the same vertex set is asymptotically equivalent to a random regular graph of the combined degree, provided it grows as the number of vertices…

Combinatorics · Mathematics 2024-07-29 Mikhail Isaev , Brendan D. McKay , Angus Southwell , Maksim Zhukovskii

We study the asymptotic number of certain monotonically labeled increasing trees arising from a generalized evolution process. The main difference between the presented model and the classical model of binary increasing trees is that the…

Combinatorics · Mathematics 2019-10-30 Olivier Bodini , Antoine Genitrini , Bernhard Gittenberger , Stephan Wagner

For a simple graph $G=(V,E)$ and edge $e\in E$, the effective resistance is defined as a ratio $\frac{\tau(G/e)}{\tau(G)}$, where $\tau(G)$ denotes the number of spanning trees in $G$. We resolve the inverse problem for the effective…

Combinatorics · Mathematics 2025-05-27 Swee Hong Chan , Alex Kontorovich , Igor Pak

The sequence A120986 in the Encyclopedia of Integer Sequences counts ternary trees according to the number of nodes and the number of middle edges. Using a certain substition, the underlying cubic equation can be factored. This leads to an…

Combinatorics · Mathematics 2020-09-16 Helmut Prodinger

Let $\mathcal{G}_{n,r,s}$ denote a uniformly random $r$-regular $s$-uniform hypergraph on the vertex set $\{1,2,\ldots, n\}$. We establish a threshold result for the existence of a spanning tree in $\mathcal{G}_{n,r,s}$, restricting to $n$…

Combinatorics · Mathematics 2023-06-22 Catherine Greenhill , Mikhail Isaev , Gary Liang

Much information about a graph can be obtained by studying its spanning trees. On the other hand, a graph can be regarded as a 1-dimensional cell complex, raising the question of developing a theory of trees in higher dimension. As observed…

Combinatorics · Mathematics 2015-06-24 Art M. Duval , Caroline J. Klivans , Jeremy L. Martin

Singerman introduced to the theory of maps on surfaces an object that is a universal cover for any map. This object is a tessellation of the hyperbolic plane together with a certain subset of the ideal boundary. The 1-skeleton of this…

Number Theory · Mathematics 2015-08-07 Ian Short , Mairi Walker

In this paper, we present some new results describing connections between the spectrum of a regular graph and its generalized connectivity, toughness, and the existence of spanning trees with bounded degree.

Combinatorics · Mathematics 2016-02-19 Sebastian M. Cioabă , Xiaofeng Gu

We examine a pair of dynamical systems on the plane induced by a pair of spanning trees in the Cayley graph of the Super-Apollonian group of Graham, Lagarias, Mallows, Wilks and Yan. The dynamical systems compute Gaussian rational…

Number Theory · Mathematics 2017-05-03 Sneha Chaubey , Elena Fuchs , Robert Hines , Katherine E. Stange

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

The Fibonacci numbers are the prototypical example of a recursive sequence, but grow too quickly to enumerate sets of integer partitions. The same is true for the other classical sequences $a(n)$ defined by Fibonacci-like recursions: the…

Combinatorics · Mathematics 2023-03-22 Cristina Ballantine , George Beck

Trees are partial orders in which every element has a linearly ordered set of predecessors. Here we initiate the exploration of the structural theory of trees with the study of different notions of \emph{branching in trees} and of…

Combinatorics · Mathematics 2023-01-18 Valentin Goranko , Ruaan Kellerman , Alberto Zanardo

We consider an infinite sequence of rooted trees naturally emerging in a number-theoretical context. We advance some ideas on its structure by discussing some elementary properties. Some of those properties are shown to be related to…

Number Theory · Mathematics 2023-01-10 Roberto Conti , Pierluigi Contucci

We give a short proof of Cayley's tree formula for counting the number of different labeled trees on $n$ vertices. The following nonlinear recursive relation for the number of labeled trees on $n$ vertices is deduced from a combinatorial…

Combinatorics · Mathematics 2022-12-22 Alok Bhushan Shukla

We prove two estimates for the expectation of the exponential of a complex function of a random permutation or subset. Using this theory, we find asymptotic expressions for the expected number of copies and induced copies of a given graph…

Combinatorics · Mathematics 2021-07-01 Catherine Greenhill , Mikhail Isaev , Brendan D. McKay

We provide a combinatorial approach to counting the number of spanning trees at the $n$-th layer of a branched $\mathbb{Z}_p$-cover of a finite connected graph $\mathsf{X}$. Our method achieves in explaining how the position of the ramified…

Combinatorics · Mathematics 2025-08-22 Debanjana Kundu , Katharina Mueller

This paper is devoted to a systematic study of a class of binary trees encoding the structure of rational numbers both from arithmetic and dynamical point of view. The paper is divided into two parts. The first one is a critical review of…

Dynamical Systems · Mathematics 2008-05-16 Claudio Bonanno , Stefano Isola

Konig's theorem states that the covering number and the matching number of a bipartite graph are equal. We prove a generalisation of this result, in which each point in one side of the graph is replaced by a subtree of a given tree. The…

Combinatorics · Mathematics 2007-05-23 Ron Aharoni , Eli Berger , Ran Ziv

A bipartite graph $G=(A, B, E)$ is said to be a biconvex bipartite graph if there exist orderings $<_A$ in $A$ and $<_B$ in $B$ such that the neighbors of every vertex in $A$ are consecutive with respect to $<_B$ and the neighbors of every…

Combinatorics · Mathematics 2024-06-04 Dhanyamol Antony , Anita Das , Shirish Gosavi , Dalu Jacob , Shashanka Kulamarva

In a partially ordered semigroup with the duality (or polarity) transform, it is possible to define a generalisation of continued fractions. General sufficient conditions for convergence of continued fractions with deterministic terms are…

Metric Geometry · Mathematics 2014-09-08 Ilya Molchanov