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Related papers: A note on the size of query trees

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In this short note we discuss recent results on hook length formulas of trees unifying some earlier results, and explain hook length formulas naturally associated to families of increasingly labelled trees.

Combinatorics · Mathematics 2010-04-13 Markus Kuba

We give an algorithm that for an input n-vertex graph G and integer k>0, in time 2^[O(k)]n either outputs that the treewidth of G is larger than k, or gives a tree decomposition of G of width at most 5k+4. This is the first algorithm…

Data Structures and Algorithms · Computer Science 2013-04-24 Hans Bodlaender , Pål G. Drange , Markus S. Dregi , Fedor V. Fomin , Daniel Lokshtanov , Michał Pilipczuk

We show that a randomly perturbed digraph, where we start with a dense digraph $D_\alpha$ and add a small number of random edges to it, will typically contain a fixed orientation of a bounded degree spanning tree. This answers a question…

Combinatorics · Mathematics 2024-08-21 Patryk Morawski , Kalina Petrova

We look for partition theorems for large subtrees for suitable uncountable trees and colourings. We concentrate on sub-trees of $^{\kappa \ge} 2$ expanded by a well ordering of each level. Unlike earlier works, we do not ask the embedding…

Logic · Mathematics 2026-01-06 Saharon Shelah

Geometry of networks endowed with a causal structure is discussed using the conventional framework of equilibrium statistical mechanics. The popular growing network models appear as particular causal models. We focus on a class of tree…

Statistical Mechanics · Physics 2009-11-07 P. Bialas , Z. Burda , J. Jurkiewicz , A. Krzywicki

When $H$ is a forest, the Gy\'arf\'as-Sumner conjecture implies that every graph $G$ with no induced subgraph isomorphic to $H$ and with bounded clique number has a stable set of linear size. We cannot prove that, but we prove that every…

Combinatorics · Mathematics 2025-07-21 Tung Nguyen , Alex Scott , Paul Seymour

Motivated by the study of random temporal networks, we introduce a class of random trees that we coin \emph{uniform temporal trees}. A uniform temporal tree is obtained by assigning independent uniform $[0,1]$ labels to the edges of a…

Probability · Mathematics 2025-01-23 Caelan Atamanchuk , Luc Devroye , Gabor Lugosi

This paper deals with the size of the spanning tree of p randomly chosen nodes in a binary search tree. It is shown via generating functions methods, that for fixed p, the (normalized) spanning tree size converges in law to the Normal…

Probability · Mathematics 2007-05-23 Alois Panholzer , Helmut Prodinger

A \emph{queue layout} of a graph consists of a total order of the vertices, and a partition of the edges into \emph{queues}, such that no two edges in the same queue are nested. The minimum number of queues in a queue layout of a graph is…

Discrete Mathematics · Computer Science 2011-10-05 Vida Dujmovic , Pat Morin , David R. Wood

We study two problems that seek a subtree $T$ of a graph $G=(V,E)$ such that $T$ satisfies a certain property and has minimal maximum degree. - In the Min-Degree Group Steiner Tree problem we are given a collection ${\cal S}$ of groups…

Data Structures and Algorithms · Computer Science 2019-10-29 Guy Kortsarz , Zeev Nutov

We study separating systems of the edges of a graph where each member of the separating system is a path. We conjecture that every $n$-vertex graph admits a separating path system of size $O(n)$ and prove this in certain interesting special…

Empirical observations suggest that in pure even-aged forests, the mean diameter of forest trees (D, diameter at breast height, 1.3 m above ground) tends to remain a constant proportion of stand height (H, average height of the largest…

Quantitative Methods · Quantitative Biology 2009-08-23 Jerome K Vanclay

Let $F(G)$ be the number of forests of a graph $G$. Similarly let $C(G)$ be the number of connected spanning subgraphs of a connected graph $G$. We bound $F(G)$ and $C(G)$ for regular graphs and for graphs with fixed average degree. Among…

Combinatorics · Mathematics 2021-08-03 Márton Borbényi , Péter Csikvári , Haoran Luo

The metric dimension of a graph is the size of the smallest set of vertices whose distances distinguish all pairs of vertices in the graph. We show that this graph invariant may be calculated by an algorithm whose running time is linear in…

Data Structures and Algorithms · Computer Science 2015-06-11 David Eppstein

A \emph{tree-partition} of a graph $G$ is a proper partition of its vertex set into `bags', such that identifying the vertices in each bag produces a forest. The \emph{tree-partition-width} of $G$ is the minimum number of vertices in a bag…

Combinatorics · Mathematics 2009-04-02 David R. Wood

The size-Ramsey number of a graph $G$ is the minimum number of edges in a graph $H$ such that every 2-edge-coloring of $H$ yields a monochromatic copy of $G$. Size-Ramsey numbers of graphs have been studied for almost 40 years with…

Combinatorics · Mathematics 2015-03-24 Andrzej Dudek , Steven La Fleur , Dhruv Mubayi , Vojtech Rodl

A tree with at most k leaves is called k-ended tree, and a tree with exactly k leaves is called k-end tree, where a leaf is a vertex of degree one. Contraction of a graph G along the edge e means deleting the edge e and identifying its end…

Combinatorics · Mathematics 2016-12-30 Hamed Ghasemian Zoeram

We prove that any graph $G$ with $n$ points has a distribution $\mathcal{T}$ over spanning trees such that for any edge $(u,v)$ the expected stretch $E_{T \sim \mathcal{T}}[d_T(u,v)/d_G(u,v)]$ is bounded by $\tilde{O}(\log n)$. Our result…

Data Structures and Algorithms · Computer Science 2008-08-15 Ittai Abraham , Yair Bartal , Ofer Neiman

We study the component structure of the random graph $G=G_{n,m,d}$. Here $d=O(1)$ and $G$ is sampled uniformly from ${\mathcal G}_{n,m,d}$, the set of graphs with vertex set $[n]$, $m$ edges and maximum degree at most $d$. If $m=\mu n/2$…

Combinatorics · Mathematics 2021-06-04 Alan Frieze , Tomasz Tkocz

The problem of spanning trees is closely related to various interesting problems in the area of statistical physics, but determining the number of spanning trees in general networks is computationally intractable. In this paper, we perform…

Statistical Mechanics · Physics 2012-04-23 Zhongzhi Zhang , Bin Wu , Yuan Lin