English
Related papers

Related papers: Which point sets admit a k-angulation?

200 papers

A plane graph is l-facially k-colourable if its vertices can be coloured with k colours such that any two distinct vertices on a facial segment of length at most l are coloured differently. We prove that every plane graph is 3-facially…

Discrete Mathematics · Computer Science 2016-08-16 Fédéric Havet , Jean-Sébastien Sereni , Riste Skrekovski

Given $2k-1$ convex sets in $R^2$ such that no point of the plane is covered by more than $k$ of the sets, is it true that there are two among the convex sets whose union contains all $k$-covered points of the plane? This question due to…

Combinatorics · Mathematics 2019-12-18 Adam S. Jobson , André E. Kézdy , Jenő Lehel , Timothy J. Pervenecki , Géza Tóth

Let S be a set of n >= d points in general position in R^d. An oriented (d-1)-simplex spanned by d points from S is called a k-facet iff the positive side of its affine hull contains exactly k points from S. A (<=k)-facet is simply an…

Computational Geometry · Computer Science 2017-01-16 James King

Let $G=(V,E)$ be a simple graph. A set $I\subseteq V$ is an independent set, if no two of its members are adjacent in $G$. The $k$-independent graph of $G$, $I_k (G)$, is defined to be the graph whose vertices correspond to the independent…

Combinatorics · Mathematics 2020-01-03 Davood Fatehi , Saeid Alikhani , Abdul Jalil M. Khalaf

A simple topological graph $G$ is a graph drawn in the plane so that any pair of edges have at most one point in common, which is either an endpoint or a proper crossing. $G$ is called saturated if no further edge can be added without…

Combinatorics · Mathematics 2015-01-30 Jan Kynčl , János Pach , Radoš Radoičić , Géza Tóth

A graph is $k$-planar $(k \geq 1)$ if it can be drawn in the plane such that no edge is crossed more than $k$ times. A graph is $k$-quasi planar $(k \geq 2)$ if it can be drawn in the plane with no $k$ pairwise crossing edges. The families…

A dominating set of a graph $G$ is a subset $S$ of its vertices such that each vertex of $G$ not in $S$ has a neighbor in $S$. A face-hitting set of a plane graph $G$ is a set $T$ of vertices in $G$ such that every face of $G$ contains at…

Combinatorics · Mathematics 2024-03-06 P. Francis , Abraham M. Illickan , Lijo M. Jose , Deepak Rajendraprasad

A generalized pentagonal geometry PENT($k$,$r$,$w$) is a partial linear space, where every line is incident with $k$ points, every point is incident with $r$ lines, and for each point, $x$, the set of points not collinear with $x$ forms the…

Combinatorics · Mathematics 2023-01-10 Anthony D. Forbes , Carrie G. Rutherford

Motivated by a result of [1] which states that if F is a subgraph of a convex complete graph K_n and F contains no boundary edge of K_n and |E(F)| \leq n-3, then K_n - F admits a triangulation, we determine necessary and sufficient…

Combinatorics · Mathematics 2016-11-29 Niran Abbas Ali , Gek L. Chia , Hazim Michman Trao , Adem Kilicman

Given a set S of n points in R^D, and an integer k such that 0 <= k < n, we show that a geometric graph with vertex set S, at most n - 1 + k edges, maximum degree five, and dilation O(n / (k+1)) can be computed in time O(n log n). For any…

Computational Geometry · Computer Science 2009-12-07 Boris Aronov , Mark de Berg , Otfried Cheong , Joachim Gudmundsson , Herman Haverkort , Michiel Smid , Antoine Vigneron

Suppose $G$ is a undirected simple graph. A $k-$subset of edges in $G$ without common vertices is called a $k-$matching and the number of such subsets is denoted by $p(G,k)$. The aim of this paper is to present exact formulas for $p(G,3)$,…

Combinatorics · Mathematics 2021-07-12 Kinkar Ch. Das , Ali Ghalavand , Ali Reza Ashrafi

Given a finite set of points $S\subset\mathbb{R}^d$, a $k$-set of $S$ is a subset $A \subset S$ of size $k$ which can be strictly separated from $S \setminus A $ by a hyperplane. Similarly, a $k$-facet of a point set $S$ in general position…

Metric Geometry · Mathematics 2022-03-23 Brett Leroux , Luis Rademacher

In this paper we study properties of intersection graphs of k-bend paths in the rectangular grid. A k-bend path is a path with at most k 90 degree turns. The class of graphs representable by intersections of k-bend paths is denoted by…

Computational Geometry · Computer Science 2012-06-25 Steven Chaplick , Vít Jelínek , Jan Kratochvíl , Tomáš Vyskočil

A collection $ \Delta $ of simple closed curves on an orientable surface is an algebraic $ k $-system if the algebraic intersection number $\langle \alpha,\beta \rangle$ is equal to $k $ in absolute value for every $ \alpha , \beta \in…

Geometric Topology · Mathematics 2020-02-17 Charles Daly , Jonah Gaster , Max Lahn , Aisha Mechery , Simran Nayak

A graph drawn in the plane is called k-quasi-planar if it does not contain k pairwise crossing edges. It has been conjectured for a long time that for every fixed k, the maximum number of edges of a k-quasi-planar graph with n vertices is…

Combinatorics · Mathematics 2011-12-13 Jacob Fox , Janos Pach , Andrew Suk

A graph is universally $k$-edge-weightable if for every $k$-element set $Q\subset\mathbb{R}$, it admits a proper $Q$-edge weighting. The settled 1-2-3 conjecture implies that for any arithmetic progression $\{a,b,c\}$, every nice regular…

Combinatorics · Mathematics 2026-02-16 Kecai Deng

We consider a variation of the classical Erd\H{o}s-Szekeres problems on the existence and number of convex $k$-gons and $k$-holes (empty $k$-gons) in a set of $n$ points in the plane. Allowing the $k$-gons to be non-convex, we show bounds…

Some graphs admit drawings in the Euclidean k-space in such a (natu- ral) way, that edges are represented as line segments of unit length. Such drawings will be called k dimensional unit distance representations. When two non-adjacent…

Combinatorics · Mathematics 2010-01-07 Jan Kratochvil , Boris Horvat , Tomaz Pisanski

A string graph is an intersection graph of curves in the plane. A $k$-string graph is a graph with a string representation in which every pair of curves intersects in at most $k$ points. We introduce the class of $(=k)$-string graphs as a…

Combinatorics · Mathematics 2023-08-31 Petr Chmel , Vít Jelínek

We present a new model for hybrid planarity that relaxes existing hybrid representations. A graph $G = (V,E)$ is $(k,p)$-planar if $V$ can be partitioned into clusters of size at most $k$ such that $G$ admits a drawing where: (i) each…

Data Structures and Algorithms · Computer Science 2018-09-25 Emilio Di Giacomo , William J. Lenhart , Giuseppe Liotta , Timothy W. Randolph , Alessandra Tappini