English
Related papers

Related papers: Improving Lower Bound on Opaque Set for Equilatera…

200 papers

Let G be a graph that may be drawn in the plane in such a way that all internal faces are centrally symmetric convex polygons. We show how to find a drawing of this type that maximizes the angular resolution of the drawing, the minimum…

Data Structures and Algorithms · Computer Science 2009-08-03 David Eppstein , Kevin A. Wortman

In 1996, Matheson and Tarjan proved that every near planar triangulation on $n$ vertices contains a dominating set of size at most $n/3$, and conjectured that this upper bound can be reduced to $n/4$ for planar triangulations when $n$ is…

Combinatorics · Mathematics 2023-08-08 Fábio Botler , Cristina G. Fernandes , Juan Gutiérrez

The first nonzero eigenvalue of the Neumann Laplacian is shown to be minimal for the degenerate acute isosceles triangle, among all triangles of given diameter. Hence an optimal Poincar\'{e} inequality for triangles is derived. The proof…

Spectral Theory · Mathematics 2009-07-10 R. Laugesen , B. Siudeja

We introduce remarkable upper bounds for the interpolation error constants on triangles, which are sharp and given by simple formulas. These constants are crucial in analyzing interpolation errors, particularly those associated with the…

Numerical Analysis · Mathematics 2025-07-18 Kenta Kobayashi

We give an explicitly computable lower bound for the arithmetic self-intersection number of the dualizing sheaf on a large class of arithmetic surfaces. If some technical conditions are satisfied, then this lower bound is positive. In…

Number Theory · Mathematics 2013-07-22 Ulf Kühn , Jan Steffen Müller

In this paper, we provide tight lower bounds for the oracle complexity of minimizing high-order H\"older smooth and uniformly convex functions. Specifically, for a function whose $p^{th}$-order derivatives are H\"older continuous with…

Optimization and Control · Mathematics 2025-06-10 Cedar Site Bai , Brian Bullins

Assume $G$ is a bridgeless graph. A cycle cover of $G$ is a collection of cycles of $G$ such that each edge of $G$ is contained in at least one of the cycles. The length of a cycle cover of $G$ is the sum of the lengths of the cycles in the…

Combinatorics · Mathematics 2025-01-07 Deping Song , Xuding Zhu

Given a set $\mathcal{P}$ of $h$ pairwise disjoint simple polygonal obstacles in $\mathbb{R}^2$ defined with $n$ vertices, we compute a sketch $\Omega$ of $\mathcal{P}$ whose size is independent of $n$, depending only on $h$ and the input…

Computational Geometry · Computer Science 2019-09-17 R Inkulu , Sanjiv Kapoor

An upper bound for the Lebesgue constant (the supremum norm) of the operator of interpolation of a function in equally spaced points of a triangle by a polynomial of total degree less than or equal to n is obtained. Earlier, the rate of…

Numerical Analysis · Mathematics 2022-09-22 N Baidakova

The equality constraint a+b+c=1 for random triangle sides corresponds to breaking a stick in two places. An analog a^2+b^2+c^2=1 has a remarkable feature: the bivariate density for angles coincides with that for 3D Gaussian triangles.…

Probability · Mathematics 2014-12-01 Steven R. Finch

A triangulation of a surface is k-irreducible if every non-contractible curve has length at least k and any edge contraction breaks this property. Equivalently, every edge belongs to a non-contractible curve of length k and there are no…

Computational Geometry · Computer Science 2026-05-18 Vincent Delecroix , Oscar Fontaine , Arnaud de Mesmay

The present paper aims to solve some problems proposed by Lassak about the reduced spherical polygons. The main result is to show that the regular spherical n-gon has the minimal perimeter among all reduced spherical polygons of fixed…

Metric Geometry · Mathematics 2022-04-14 Cen Liu , Yanxun Chang

Minimal linear codes are in one-to-one correspondence with special types of blocking sets of projective spaces over a finite field, which are called strong or cutting blocking sets. In this paper we prove an upper bound on the minimal…

Combinatorics · Mathematics 2021-05-18 Tamás Héger , Zoltán Lóránt Nagy

A high-level description of an algorithm which computes the minimum perimeter triangle enclosing a convex polygon in linear time exists in the literature. Besides that an implementation of the algorithm is given in the subsequent work.…

Metric Geometry · Mathematics 2016-06-08 V. Ermolaev

We derive and implement a new way to find lower bounds on the smallest limiting trace-to-degree ratio of totally positive algebraic integers and improve the previously best known bound to 1.80203. Our method adds new constraints to Smyth's…

Number Theory · Mathematics 2024-09-26 Bryce Joseph Orloski , Naser Talebizadeh Sardari , Alexander Smith

An oblivious subspace embedding (OSE) for some eps, delta in (0,1/3) and d <= m <= n is a distribution D over R^{m x n} such that for any linear subspace W of R^n of dimension d, Pr_{Pi ~ D}(for all x in W, (1-eps) |x|_2 <= |Pi x|_2 <=…

Discrete Mathematics · Computer Science 2013-08-19 Jelani Nelson , Huy L. Nguyen

Let $S$ be a finite set of points in the Euclidean plane. Let $D$ be a Delaunay triangulation of $S$. The {\em stretch factor} (also known as {\em dilation} or {\em spanning ratio}) of $D$ is the maximum ratio, among all points $p$ and $q$…

Computational Geometry · Computer Science 2013-08-30 Ge Xia

Let $E(k, \ell)$ denote the smallest integer such that any set of at least $E(k, \ell)$ points in the plane, no three on a line, contains either an empty convex polygon with $k$ vertices or an empty pseudo-triangle with $\ell$ vertices. The…

Combinatorics · Mathematics 2012-10-18 Bhaswar B. Bhattacharya , Sandip Das

In this survey article, we are interested on minimal triangulations of closed pl manifolds. We present a brief survey on the works done in last 25 years on the following: (i) Finding the minimal number of vertices required to triangulate a…

Geometric Topology · Mathematics 2007-05-23 Basudeb Datta

Let $p\geq3$ be a large prime and let $n(p)\geq2$ denotes the least quadratic nonresidue modulo $p$. This note sharpens the standard upper bound of the least quadratic nonresidue from the unconditional upper bound $n(p)\ll…

General Mathematics · Mathematics 2025-10-10 N. A. Carella