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Related papers: Lower bounds for the simplexity of the n-cube

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Triangulations of the cube into a minimal number of simplices without additional vertices have been studied by several authors over the past decades. For $3\leq n\leq 7$ this so-called simplexity of the unit cube $I^n$ is now known to be…

Combinatorics · Mathematics 2012-09-19 Jan Brandts , Sander Dijkhuis , Vincent de Haan , Michal Křížek

We show that the size of a minimal simplicial cover of a polytope $P$ is a lower bound for the size of a minimal triangulation of $P$, including ones with extra vertices. We then use this fact to study minimal triangulations of cubes, and…

Combinatorics · Mathematics 2007-05-23 Adam Bliss , Francis Edward Su

It is verified that the number of vertices in a $d$-dimensional cubical pseudomanifold is at least $2^{d+1}$. Using Adin's cubical $h$-vector, the generalized lower bound conjecture is established for all cubical 4-spheres, as well as for…

Combinatorics · Mathematics 2011-04-05 Steven Klee

It is well-known that the triangulations of the disc with $n+2$ vertices on its boundary are counted by the $n$th Catalan number $C(n)=\frac{1}{n+1}{2n \choose n}$. This paper deals with the generalisation of this problem to any arbitrary…

Combinatorics · Mathematics 2012-03-14 Olivier Bernardi , Juanjo Rué

We show that the minimum number of vertices of a simplicial complex with fundamental group $\mathbb{Z}^{n}$ is at most $O(n)$ and at least $\Omega(n^{3/4})$. For the upper bound, we use a result on orthogonal 1-factorizations of $K_{2n}$.…

Combinatorics · Mathematics 2021-09-27 Florian Frick , Matt Superdock

In the present paper we find a bijection between the set of small covers over an $n$-cube and the set of acyclic digraphs with $n$ labeled nodes. Using this, we give a formula of the number of small covers over an $n$-cube (generally, a…

Geometric Topology · Mathematics 2014-10-01 Suyoung Choi

Products of simplices, called simplotopes, and their triangulations arise naturally in algorithmic applications in game theory and optimization. We develop techniques to derive lower bounds for the size of simplicial covers and…

Combinatorics · Mathematics 2017-07-19 Tyler Seacrest , Francis Edward Su

This paper studies the minimal number of vertices $\lambda(n,d)$ required in a triangulation of the $n$-sphere to admit a simplicial map to the boundary of a $(n+1)$-simplex with a given degree $d$. We establish upper bounds for…

Combinatorics · Mathematics 2026-01-21 Ksenia Apolonskaya , Oleg R. Musin

A combinatorial theorem on families of disjoint sub-boxes of a discrete cube, which implies that there at most $2^{d+1}-2$ neighbourly simplices in $\mathbb R^d$, is presented.

Combinatorics · Mathematics 2019-02-18 Andrzej P. Kisielewicz , Krzysztof Przesławski

It has been shown that the $n$-dimensional unit hypercube contains an $n$-dimensional regular simplex of edge length $c\sqrt n$ for arbitrary $c<1/2$ if $n$ is sufficiently large (Maehara, Ruzsa and Tokushige, 2009). We prove the same…

Metric Geometry · Mathematics 2011-01-17 Hiroki Tamura

For each $1\leq i \le n$, let $k_i\geq 1$ and let $\Delta_i$ be a set of vertices of a non-degenerate simplex of $k_i+1$ points in $\mathbb{R}^{k_i+1}$. If $A\subseteq [0,1]^{k_1+1}\times \cdots \times [0,1]^{k_n+1}$ is a Lebesgue…

Combinatorics · Mathematics 2022-06-22 Polona Durcik , Mario Stipčić

For any positive integer $n$, the author previously constructed several minimal simplicial $n$-complexes which necessarily contain a non-splittable two-component link, consisting of an $(n-1)$-sphere and an $n$-sphere, in any embedding into…

Geometric Topology · Mathematics 2026-05-28 Ryo Nikkuni

We show that any point in the convex hull of each of (d+1) sets of (d+1) points in general position in \R^d is contained in at least (d+1)^2/2 simplices with one vertex from each set. This improves the known lower bounds for all d >= 4.

Combinatorics · Mathematics 2010-06-01 Antoine Deza , Tamon Stephen , Feng Xie

We prove that at least $\Omega(n^{0.51})$ hyperplanes are needed to slice all edges of the $n$-dimensional hypercube. We provide a couple of applications: lower bounds on the computational complexity of parity, and a lower bound on the…

Combinatorics · Mathematics 2021-02-18 Gal Yehuda , Amir Yehudayoff

We introduce the non-pure versions of simplicial balls and spheres with minimum number of vertices. These are a special type of non-homogeneous balls and spheres (NH-balls and NH-spheres) satisfying a minimality condition on the number of…

Combinatorics · Mathematics 2014-06-26 Nicolas Ariel Capitelli

By studying the volume of a generalized difference body, this paper presents the first nontrivial lower bound for the lattice covering density by $n$-dimensional simplices.

Metric Geometry · Mathematics 2015-02-17 Fei Xue , Chuanming Zong

We show that for the regular n-simplex, the 1-codimensional central slice that's parallel to a facet will achieve the minimum area (up to a 1-o(1) factor) among all 1-codimensional central slices, thus improving the previous best known…

Metric Geometry · Mathematics 2024-06-24 Colin Tang

We prove a combinatorial theorem on families of disjoint sub-boxes of a discrete cube, which implies that there are at most $2^{d+1}-2$ nearly neighbourly simplices in $\mathbb R^d$.

Combinatorics · Mathematics 2020-01-01 Andrzej P. Kisielewicz , Krzysztof Przesławski

Consider the $n$-cube graph with vertices $\{-1,1\}^n$ and edges connecting vertices with hamming distance $1$. How many hyperplanes in $\mathbb{R}^n$ are needed in order to dissect all edges? We show that at least…

Combinatorics · Mathematics 2022-12-23 Ohad Klein

A subset of vertices in a graph $G$ is considered a maximal dissociation set if it induces a subgraph with vertex degree at most 1 and it is not contained within any other dissociation sets. In this paper, it is shown that for $n\geq 3$,…

Combinatorics · Mathematics 2024-11-06 Junxia Zhang , Xiangyu Ren , Maoqun Wang
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