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Related papers: Monotone Paths in Geometric Triangulations

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We show that the maximum number of convex polygons in a triangulation of $n$ points in the plane is $O(1.5029^n)$. This improves an earlier bound of $O(1.6181^n)$ established by van Kreveld, L\"offler, and Pach (2012) and almost matches the…

Metric Geometry · Mathematics 2017-08-10 Adrian Dumitrescu , Csaba D. Tóth

Motivated by trying to understand the behavior of the simplex method, Athanasiadis, De Loera and Zhang provided upper and lower bounds on the number of the monotone paths on 3-polytopes. For simple 3-polytopes with $2n$ vertices, they…

Combinatorics · Mathematics 2025-08-05 François Clément , Dan Guyer

We study the maximal number of triangulations that a planar set of $n$ points can have, and show that it is at most $30^n$. This new bound is achieved by a careful optimization of the charging scheme of Sharir and Welzl (2006), which has…

Discrete Mathematics · Computer Science 2010-01-03 Micha Sharir , Adam Sheffer

We give upper and lower bounds on the maximum and minimum number of geometric configurations of various kinds present (as subgraphs) in a triangulation of $n$ points in the plane. Configurations of interest include \emph{convex polygons},…

Combinatorics · Mathematics 2015-09-22 Adrian Dumitrescu , Maarten Löffler , André Schulz , Csaba D. Tóth

We prove polynomial upper bounds of geometric Ramsey numbers of pathwidth-2 outerplanar triangulations in both convex and general cases. We also prove that the geometric Ramsey numbers of the ladder graph on $2n$ vertices are bounded by…

Combinatorics · Mathematics 2015-09-14 Josef Cibulka , Pu Gao , Marek Krčál , Tomáš Valla , Pavel Valtr

We obtain new lower and upper bounds for the maximum multiplicity of some weighted and, respectively, non-weighted common geometric graphs drawn on n points in the plane in general position (with no three points collinear): perfect…

Discrete Mathematics · Computer Science 2011-09-27 Adrian Dumitrescu , André Schulz , Adam Sheffer , Csaba D. Tóth

In 1962, Tutte provided a formula for the number of combinatorial triangulations, that is, maximal planar graphs with a fixed triangular face and $n$ additional vertices. In this note, we study how many ways a combinatorial triangulation…

Combinatorics · Mathematics 2025-04-25 Belén Cruces , Clemens Huemer , Dolores Lara

Given a point $s$ and a set of $h$ pairwise disjoint polygonal obstacles of totally $n$ vertices in the plane, we present a new algorithm for building an $L_1$ shortest path map of size O(n) in $O(T)$ time and O(n) space such that for any…

Computational Geometry · Computer Science 2012-02-28 Danny Z. Chen , Haitao Wang

Let $G$ be a fixed graph. Two paths of length $n-1$ on $n$ vertices (Hamiltonian paths) are $G$-different if there is a subgraph isomorphic to $G$ in their union. In this paper we prove that the maximal number of pairwise triangle-different…

Combinatorics · Mathematics 2016-10-13 István Kovács , Dániel Soltész

How long a monotone path can one always find in any edge-ordering of the complete graph $K_n$? This appealing question was first asked by Chv\'atal and Koml\'os in 1971, and has since attracted the attention of many researchers, inspiring a…

Combinatorics · Mathematics 2019-09-20 Matija Bucic , Matthew Kwan , Alexey Pokrovskiy , Benny Sudakov , Tuan Tran , Adam Zsolt Wagner

The number of triangulations of a planar n point set is known to be $c^n$, where the base $c$ lies between $2.43$ and $30.$ The fastest known algorithm for counting triangulations of a planar n point set runs in $O^*(2^n)$ time. The fastest…

Computational Geometry · Computer Science 2014-11-21 Marek Karpinski , Andrzej Lingas , Dzmitry Sledneu

Let $f(n,H)$ denote the maximum number of copies of $H$ in an $n$-vertex planar graph. The order of magnitude of $f(n,P_k)$, where $P_k$ is a path on $k$ vertices, is $n^{{\lfloor{\frac{k-1}{2}}\rfloor}+1}$. In this paper we determine the…

Combinatorics · Mathematics 2021-10-18 Debarun Ghosh , Ervin Győri , Ryan R. Martin , Addisu Paulos , Nika Salia , Chuanqi Xiao , Oscar Zamora

We shall study degree-monotone paths in graphs, a problem inspired by the celebrated theorem of Erd{\H{o}}s-Szekeres concerning the longest monotone subsequence of a given sequence of numbers. A path P in a graph G is said to be a degree…

Combinatorics · Mathematics 2014-05-09 Yair Caro , Josef Lauri , Christina Zarb

Let $G$ be an intersection graph of $n$ geometric objects in the plane. We show that a maximum matching in $G$ can be found in $O(\rho^{3\omega/2}n^{\omega/2})$ time with high probability, where $\rho$ is the density of the geometric…

Computational Geometry · Computer Science 2024-05-02 Édouard Bonnet , Sergio Cabello , Wolfgang Mulzer

Any simple planar graph can be triangulated, i.e., we can add edges to it, without adding multi-edges, such that the result is planar and all faces are triangles. In this paper, we study the problem of triangulating a planar graph without…

Discrete Mathematics · Computer Science 2015-05-19 Therese Biedl

A path system in a graph $G$ is a collection of paths, with exactly one path between any two vertices in $G$. A path system is said to be consistent if it is intersection-closed. We show that the number of consistent path systems on $n$…

Combinatorics · Mathematics 2025-11-04 Daniel Cizma , Nati Linial

The diameter of an undirected or a directed graph is defined to be the maximum shortest path distance over all pairs of vertices in the graph. Given an undirected graph $G$, we examine the problem of assigning directions to each edge of $G$…

Data Structures and Algorithms · Computer Science 2022-03-09 Debajyoti Mondal , N. Parthiban , Indra Rajasingh

We show that a point set of cardinality $n$ in the plane cannot be the vertex set of more than $59^n O(n^{-6})$ straight-edge triangulations of its convex hull. This improves the previous upper bound of $276.75^n$.

Combinatorics · Mathematics 2007-05-23 Francisco Santos , Raimund Seidel

We study the maximum numbers of pseudo-triangulations and pointed pseudo-triangulations that can be embedded over a specific set of points in the plane or contained in a specific triangulation. We derive the bounds $O(5.45^N)$ and $\Omega…

Computational Geometry · Computer Science 2012-10-29 Moria Ben-Ner , André Schulz , Adam Sheffer

A monotone drawing of a graph G is a straight-line drawing of G such that, for every pair of vertices u,w in G, there exists abpath P_{uw} in G that is monotone in some direction l_{uw}. (Namely, the order of the orthogonal projections of…

Data Structures and Algorithms · Computer Science 2016-04-14 Dayu He , Xin He
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