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Related papers: Cutting 4 by $n$ grids into two congruent pieces

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We study the problem of partitioning a given simple polygon $P$ into a minimum number of connected polygonal pieces, each of bounded size. We describe a general technique for constructing such partitions that works for several notions of…

Computational Geometry · Computer Science 2024-10-23 Mikkel Abrahamsen , Nichlas Langhoff Rasmussen

A $3$-connected graph $G$ is essentially $4$-connected if, for any $3$-cut $S\subseteq V(G)$ of $G$, at most one component of $G-S$ contains at least two vertices. We prove that every essentially $4$-connected maximal planar graph $G$ on…

Combinatorics · Mathematics 2021-01-28 Igor Fabrici , Jochen Harant , Samuel Mohr , Jens M. Schmidt

In this paper, we explore some generalizations of a counting problem related to tilings in grids of size 2xn, which was originally posed as a question on Mathematics Stack Exchange (Question 3972905). In particular, we consider this problem…

Discrete Mathematics · Computer Science 2024-06-25 José L. Ramírez , Diego Villamizar

In this paper, we consider the problem of partitioning a polygon into a set of connected disjoint sub-polygons, each of which covers an area of a specific size. The work is motivated by terrain covering applications in robotics, where the…

Computational Geometry · Computer Science 2021-10-11 Mariusz Wzorek , Cyrille Berger , Patrick Doherty

Addressing large-scale indefinite least squares (ILS) problem poses notable computational bottlenecks in the field of numerical linear algebra. State-of-the-art iterative schemes for such problems are predominantly constructed upon the…

Numerical Analysis · Mathematics 2026-05-08 Jun Li , Lingsheng Meng

We show that any combinatorial triangulation on n vertices can be transformed into a 4-connected one using at most floor((3n - 9)/5) edge flips. We also give an example of an infinite family of triangulations that requires this many flips…

Computational Geometry · Computer Science 2015-09-09 Prosenjit Bose , Dana Jansens , André van Renssen , Maria Saumell , Sander Verdonschot

A general scheme is presented to decompose a $d$-by-$d$ unitary matrix as the product of two-level unitary matrices with additional structure and prescribed determinants. In particular, the decomposition can be done by using two-level…

Quantum Physics · Physics 2013-03-11 Chi-Kwong Li , Rebecca Roberts , Xiaoyan Yin

The CHY construction naturally associates a vector in $\mathbb{R}^{(n-3)!}$ to every 2-regular graph with $n$ vertices. Partial amplitudes in the biadjoint scalar theory are given by the inner product of vectors associated with a pair of…

Mathematical Physics · Physics 2020-01-29 Freddy Cachazo , Karen Yeats , Samuel Yusim

We solve three enumerative problems concerning families of planar maps. More precisely, we establish algebraic equations for the generating function of non-separable triangulations in which all vertices have degree at least d, for a certain…

Combinatorics · Mathematics 2009-06-18 Olivier Bernardi

The central problem of strip theory is the calculation of potential flowaround 2D sections. One particular method of solutions to this problem is conformal mapping of the body section to the unit circle over which a solution of potential…

Numerical Analysis · Mathematics 2015-03-19 Mohammad Salehi , Parviz Ghadimi , Ali Bakhshandeh Rostami

We describe a new algorithm to compute the geometric intersection number between two curves, given as edge vectors on an ideal triangulation. Most importantly, this algorithm runs in polynomial time in the bit-size of the two edge vectors.…

Geometric Topology · Mathematics 2016-05-12 Mark C. Bell , Richard C. H. Webb

The theory of partition congruences has been a fascinating and difficult subject for over a century now. In attempting to prove a given congruence family, multiple possible complications include the genus of the underlying modular curve,…

Number Theory · Mathematics 2022-11-22 Nicolas Allen Smoot

Kernel methods for solving partial differential equations on surfaces have the advantage that those methods work intrinsically on the surface and yield high approximation rates if the solution to the partial differential equation is smooth…

Numerical Analysis · Mathematics 2024-10-04 Thomas Hangelbroek , Christian Rieger

In the present popular science paper we determine when a square can be dissected into rectangles similar to a given rectangle. The approach to the question is based on a physical interpretation using electrical networks. Only secondary…

History and Overview · Mathematics 2018-08-14 Sergey Dorichenko , Mikhail Skopenkov

The variational grid generation method is a powerful tool for generating structured convex grids on irregular simply connected domains whose boundary is a polygonal Jordan curve. Several examples that show the accuracy of a difference…

Numerical Analysis · Mathematics 2011-10-26 F. Domínguez-Mota , M. Equihua , S. Mendoza , J. G. Tinoco-Ruiz

To divide a cake into equal sized pieces most people use a knife and a mixture of luck and dexterity. These attempts are often met with varying success. Through precise geometric constructions performed with the knife replacing Euclid's…

History and Overview · Mathematics 2021-07-13 Alexander Müller-Hermes

The d-Cut problem is to decide if a graph has an edge cut such that each vertex has at most d neighbours at the opposite side of the cut. If $d=1$, we obtain the intensively studied Matching Cut problem. The d-Cut problem has been studied…

Combinatorics · Mathematics 2025-10-07 Felicia Lucke , Ali Momeni , Daniël Paulusma , Siani Smith

The cutting plane approach to optimal matchings has been discussed by several authors over the past decades (e.g., Padberg and Rao '82, Grotschel and Holland '85, Lovasz and Plummer '86, Trick '87, Fischetti and Lodi '07) and its…

Data Structures and Algorithms · Computer Science 2014-01-24 Karthekeyan Chandrasekaran , Laszlo A. Vegh , Santosh Vempala

We study how many comparability subgraphs are needed to partition the edge set of a perfect graph. We show that many classes of perfect graphs can be partitioned into (at most) two comparability subgraphs and this holds for almost all…

Combinatorics · Mathematics 2026-03-10 András Gyárfás , Márton Marits , Géza Tóth

A method is described by which a function defined on a cubic grid (as from a finite difference solution of a partial differential equation) can be resolved into spherical harmonic components at some fixed radius. This has applications to…

General Relativity and Quantum Cosmology · Physics 2010-04-06 Charles W. Misner