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Related papers: Counting Spanning Trees of Threshold Graphs

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In this work, we study the color discrepancy of spanning trees in random graphs. We show that for the Erd\H{o}s-R\'enyi random graph $G(n,p)$ with $p$ above the connectivity threshold, the following holds with high probability: in every…

Combinatorics · Mathematics 2025-11-10 Wenchong Chen , Xiao-Chuan Liu , Xu Yang

Let $G$ be a connected graph of order $n$. A spanning $k$-tree of $G$ is a spanning tree with the maximum degree at most $k$, and a spanning $k$-ended-tree of $G$ is a spanning tree at most $k$ leaves, where $k\geq2$ is an integer. This…

Combinatorics · Mathematics 2025-06-10 Jifu Lin , Zenan Du , Xinghui Zhao , Lihua You

We present a new characterization of $k$-trees based on their reduced clique graphs and $(k+1)$-line graphs, which are block graphs. We explore structural properties of these two classes, showing that the number of clique-trees of a…

Combinatorics · Mathematics 2026-02-17 Lilian Markenzon , Allana S. S. Oliveira , Cybele T. M. Vinagre

Chung and Graham considered the problem of minimizing the number of edges in an $n$-vertex graph containing all $n$-vertex trees as a subgraph. They showed that such a graph has at least $\frac{1}{2}n \log{n}$ edges. In this note, we…

Combinatorics · Mathematics 2023-11-07 Ervin Győri , Binlong Li , Nika Salia , Casey Tompkins

Given a finite planar graph, a grove is a spanning forest in which every component tree contains one or more of a specified set of vertices (called nodes) on the outer face. For the uniform measure on groves, we compute the probabilities of…

Probability · Mathematics 2011-06-30 Richard W. Kenyon , David B. Wilson

We consider lower bounds on the number of spanning trees of connected graphs with degree bounded by $d$. The question is of interest because such bounds may improve the analysis of the improvement produced by memorisation in the runtime of…

Discrete Mathematics · Computer Science 2009-02-13 John Michael Robson

For an integer $k$, a $k$-tree is a tree with maximum degree at most $k$. More generally, if $f$ is an integer-valued function on vertices, an $f$-tree is a tree in which each vertex $v$ has degree at most $f(v)$. Let $c(G)$ denote the…

Combinatorics · Mathematics 2019-07-02 M. N. Ellingham , Songling Shan , Dong Ye , Xiaoya Zha

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

Tanglegrams are special graphs that consist of a pair of rooted binary trees with the same number of leaves, and a perfect matching between the two leaf-sets. These objects are of use in phylogenetics and are represented with straightline…

Let A_n (n >= 1) be the set of all integers x such that there exists a connected graph on n vertices with precisely x spanning trees. In this paper, we show that |A_n| grows faster than sqrt{n}exp(2Pi*sqrt{n/log{n}/Sqrt(3)} This settles a…

Combinatorics · Mathematics 2012-10-24 Jernej Azarija

In the present paper we suggest a simple approach for counting Jacobian group of the $Y$-graph $Y(n; k, l, m).$ In the case $Y(n; 1, 1, 1)$ the structure of the Jacobian group will be find explicitly. Also, we obtain a closed formula for…

Combinatorics · Mathematics 2021-11-09 Y. S. Kwon , A. D. Mednykh , I. A. Mednykh

Two results (together with their relatively elementary proofs) are presented. The first one presents the upper boundary on the number of spanning trees in a finite planar multigraph, proving that the complexity (the number of spanning…

Combinatorics · Mathematics 2021-03-22 Dmitri Fomin

The crossing number of a graph is the minimum number of edge crossings that a graph can have when drawn in the plane. Determining this number, known as the Crossing Number problem, is a celebrated problem in combinatorial optimization. It…

Computational Geometry · Computer Science 2026-03-30 Petr Hliněný , Liana Khazaliya

A spanning tree of an unweighted graph is a minimum average stretch spanning tree if it minimizes the ratio of sum of the distances in the tree between the end vertices of the graph edges and the number of graph edges. We consider the…

Data Structures and Algorithms · Computer Science 2014-04-15 N. S. Narayanaswamy , G. Ramakrishna

The overlap graphs of subtrees in a tree (SOGs) generalise many other graphs classes with set representation characterisations. The complexity of recognising SOGs in open. The complexities of recognising many subclasses of SOGs are known.…

Computational Complexity · Computer Science 2022-02-04 Jessica Enright , Martin Pergel

Consider the nearest neighbor graph for the integer lattice Z^d in d dimensions. For a large finite piece of it, consider choosing a spanning tree for that piece uniformly among all possible subgraphs that are spanning trees. As the piece…

Probability · Mathematics 2007-05-23 Robin Pemantle

A tree with at most $k$ leaves is called a $k$-ended tree. A spanning 2-ended tree is a Hamilton path. A Hamilton cycle can be considered as a spanning 1-ended tree. The earliest result concerning spanning trees with few leaves states that…

Combinatorics · Mathematics 2014-09-09 Zh. G. Nikoghosyan

A tree is said to be even if for every pair of distinct leaves, the length of the unique path between them is even. In this paper we discuss the problem of determining whether an input graph has a spanning even tree. Hofmann and Walsh…

Data Structures and Algorithms · Computer Science 2024-12-24 Tesshu Hanaka , Yasuaki Kobayashi , Kazuhiro Kurita , Yasuko Matsui , Atsuki Nagao , Hirotaka Ono , Kazuhisa Seto

We introduce and study the {\em orderly spanning trees} of plane graphs. This algorithmic tool generalizes {\em canonical orderings}, which exist only for triconnected plane graphs. Although not every plane graph admits an orderly spanning…

Data Structures and Algorithms · Computer Science 2015-02-06 Yi-Ting Chiang , Ching-Chi Lin , Hsueh-I Lu

We give an asymptotic expression for the expected number of spanning trees in a random graph with a given degree sequence $\boldsymbol{d}=(d_1,\ldots, d_n)$, provided that the number of edges is at least $n + \textstyle{\frac{1}{2}}…

Combinatorics · Mathematics 2017-02-21 Catherine Greenhill , Mikhail Isaev , Matthew Kwan , Brendan D. McKay