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We show that for fixed $d>3$ and $n$ growing to infinity there are at least $(n!)^{d-2 \pm o(1)}$ different labeled combinatorial types of $d$-polytopes with $n$ vertices. This is about the square of the previous best lower bounds. As an…

Combinatorics · Mathematics 2024-04-24 Arnau Padrol , Eva Philippe , Francisco Santos

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

We show that the maximum number of pairwise intersecting positive homothets of a $d$-dimensional centrally symmetric convex body, none of which contains the center of another in its interior, is at most $3^{d+1}$. Also, we improve upper…

Metric Geometry · Mathematics 2019-04-15 Alexandr Polyanskii

Answering a question of F\"uredi and Loeb (1994), we show that the maximum number of pairwise intersecting homothets of a $d$-dimensional centrally symmetric convex body $K$, none of which contains the center of another in its interior, is…

Metric Geometry · Mathematics 2017-08-16 Márton Naszódi , János Pach , Konrad Swanepoel

In this note we show that the maximum number of vertices in any polyhedron $P=\{x\in \mathbb{R}^d : Ax\leq b\}$ with $0,1$-constraint matrix $A$ and a real vector $b$ is at most $d!$.

Computational Geometry · Computer Science 2007-05-23 Khaled Elbassioni , Zvi Lotker , Raimund Seidel

Through tropical normal idempotent matrices, we introduce isocanted alcoved polytopes, computing their $f$--vectors and checking the validity of the following five conjectures: B\'{a}r\'{a}ny, unimodality, $3^d$, flag and cubical lower…

Combinatorics · Mathematics 2020-09-30 María Jesús de la Puente , Pedro Luis Clavería

It is known that in the Minkowski sum of $r$ polytopes in dimension $d$, with $r<d$, the number of vertices of the sum can potentially be as high as the product of the number of vertices in each summand. However, the number of vertices for…

Computational Geometry · Computer Science 2010-02-02 Christophe Weibel

The paper is concerned with the linkedness of the graphs of cubical polytopes. A graph with at least $2k$ vertices is \textit{$k$-linked} if, for every set of $k$ disjoint pairs of vertices, there are $k$ vertex-disjoint paths joining the…

Combinatorics · Mathematics 2023-10-13 Hoa T. Bui , Guillermo Pineda-Villavicencio , Julien Ugon

This thesis addresses the question of the maximal number of $d$-simplices for a simplicial complex which is embeddable into $\mathbb{R}^r$ for some $d \leq r \leq 2d$. A lower bound of $f_d(C_{r + 1}(n)) =…

Combinatorics · Mathematics 2018-12-21 Anna Gundert

We derive tight expressions for the maximum number of $k$-faces, $0\le{}k\le{}d-1$, of the Minkowski sum, $P_1\oplus{}P_2$, of two $d$-dimensional convex polytopes $P_1$ and $P_2$, as a function of the number of vertices of the polytopes.…

Computational Geometry · Computer Science 2011-10-04 Menelaos I. Karavelas , Eleni Tzanaki

It is possible for a combinatorial type of polytope to have both decomposable and indecomposable realizations; here decomposability is meant with respect to Minkowski addition. Such polytopes are called conditionally decomposable. We show…

Combinatorics · Mathematics 2024-06-04 Jie Wang , David Yost

Our main result is that every n-dimensional polytope can be described by at most (2n-1) polynomial inequalities and, moreover, these polynomials can explicitly be constructed. For an n-dimensional pointed polyhedral cone we prove the bound…

Metric Geometry · Mathematics 2007-05-23 Hartwig Bosse , Martin Groetschel , Martin Henk

In this paper we investigate the problem of finding the maximum volume polytopes, inscribed in the unit sphere of the $d$-dimensional Euclidean space, with a given number of vertices. We solve this problem for polytopes with $d+2$ vertices…

Metric Geometry · Mathematics 2014-07-11 Ákos G. Horváth , Zsolt Lángi

We study the existence and structure of $d$-polytopes for which the number $f_1$ of edges is small compared to the number $f_0$ of vertices. Our results are more elegantly expressed in terms of the excess degree of the polytope, defined as…

Combinatorics · Mathematics 2024-05-28 Guillermo Pineda-Villavicencio , Jie Wang , David Yost

Let $X$ be a configuration of $n$ points in $\mathbb{R}^d$. What is the maximum number of vertices that $conv(T(X))$ can have among all the possible permissible projective transformations $T$? In this paper, we investigate this and…

Combinatorics · Mathematics 2021-07-07 Natalia García-Colín , Luis Pedro Montejano , Jorge Luis Ramírez Alfonsín

In this paper we deal with edge-to-edge, irreducible decompositions of a centrally symmetric convex $(2k)$-gon into centrally symmetric convex pieces. We prove an upper bound on the number of these decompositions for any value of $k$, and…

Metric Geometry · Mathematics 2016-02-09 Júlia Frittmann , Zsolt Lángi

We prove a lower bound theorem for the number of $k$-faces ($1\le k\le d-2$) in a $d$-dimensional polytope $P$ (or $d$-polytope) with up to $3d-1$ vertices. Previous lower bound theorems for $d$-polytopes with few vertices concern those…

Combinatorics · Mathematics 2025-12-09 Guillermo Pineda-Villavicencio , Jie Wang

In 1995, Jockusch constructed an infinite family of centrally symmetric $3$-dimensional simplicial spheres that are cs-$2$-neighborly. Here we generalize his construction and show that for all $d\geq 3$ and $n\geq d+1$, there exists a…

Combinatorics · Mathematics 2020-04-24 Isabella Novik , Hailun Zheng

For a $d$-dimensional polytope with $v$ vertices, $d+1\le v\le2d$, we calculate precisely the minimum possible number of $m$-dimensional faces, when $m=1$ or $m\ge0.62d$. This confirms a conjecture of Gr\"unbaum, for these values of $m$.…

Combinatorics · Mathematics 2019-01-17 Guillermo Pineda-Villavicencio , Julien Ugon , David Yost

We establish a lower bound theorem for the number of $k$-faces ($1\le k\le d-2$) in a $d$-dimensional polytope $P$ (abbreviated as a $d$-polytope) with $2d+2$ vertices, extending the previously known case for $k=1$. We identify all…

Combinatorics · Mathematics 2025-12-10 Guillermo Pineda-Villavicencio , Aholiab Tritama , Jie Wang , David Yost