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We show that there exist k-neighborly centrally symmetric d-dimensional polytopes with 2(n+d) vertices, where k(d,n)=Theta(d/(1+log ((d+n)/d))). We also show that this bound is tight.

组合数学 · 数学 2007-05-23 Nathan Linial , Isabella Novik

We define a centrally symmetric analogue of the cyclic polytope and study its facial structure. We conjecture that our polytopes provide asymptotically the largest number of faces in all dimensions among all centrally symmetric polytopes…

组合数学 · 数学 2007-05-23 Alexander Barvinok , Isabella Novik

We give a complete enumeration of all 2-neighborly $d$-polytopes with $d+9$ and less facets. All of them are realized as 0/1-polytopes, except a 6-polytope $P_{6,10,15}$ with 10 vertices and 15 facets, and pyramids over $P_{6,10,15}$. In…

组合数学 · 数学 2019-12-10 Aleksandr N. Maksimenko , Dmitry V. Gribanov , Dmitry S. Malyshev

We present explicit constructions of centrally symmetric 2-neighborly d-dimensional polytopes with about 3^{d/2} = (1.73)^d vertices and of centrally symmetric k-neighborly d-polytopes with about 2^{c_k d} vertices where c_k=3/20 k^2 2^k.…

度量几何 · 数学 2012-04-20 Alexander Barvinok , Seung Jin Lee , Isabella Novik

We present explicit constructions of centrally symmetric polytopes with many faces: first, we construct a d-dimensional centrally symmetric polytope P with about (1.316)^d vertices such that every pair of non-antipodal vertices of P spans…

度量几何 · 数学 2011-11-21 Alexander Barvinok , Seung Jin Lee , Isabella Novik

We define an analogue of the cube and an analogue of the 5-wedge in higher dimensions, each with $2d+2$ vertices and $d^2+2d-3$ edges. We show that these two are the only minimisers of the number of edges, amongst d-polytopes with $2d+2$…

组合数学 · 数学 2020-05-15 Guillermo Pineda-Villavicencio , Julien Ugon , David Yost

Motivated by the problem of bounding the number of rays of plane tropical curves we study the following question: Given $n\in\mathbb{N}$ and a unimodular $2$-simplex $\Delta$ what is the maximal number of vertices a lattice polytope…

组合数学 · 数学 2018-05-28 Jan-Philipp Litza , Christoph Pegel , Kirsten Schmitz

Twinned chain polytopes form a broad class of non-centrally symmetric reflexive polytopes and exhibit intriguing structures. In the present paper, we show that the number of facets of $d$-dimensional twinned chain polytopes is at most…

组合数学 · 数学 2025-12-01 Aki Mori , Kenta Mori , Hidefumi Ohsugi

Let $d \geq 3$ be an integer. It is known that the number of edges of the edge polytope of the complete graph with $d$ vertices is $d(d-1)(d-2)/2$. In this paper, we study the maximum possible number $\mu_d$ of edges of the edge polytope…

组合数学 · 数学 2018-08-22 Takayuki Hibi , Aki Mori , Hidefumi Ohsugi , Akihiro Shikama

We give an explicit construction, based on Hadamard matrices, for an infinite series of floor{sqrt{d}/2}-neighborly centrally symmetric d-dimensional polytopes with 4d vertices. This appears to be the best explicit version yet of a recent…

度量几何 · 数学 2007-05-23 Julian Pfeifle

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.

组合数学 · 数学 2019-02-18 Andrzej P. Kisielewicz , Krzysztof Przesławski

We give a complete enumeration of all 2-neighborly 0/1-polytopes of dimension 7. There are 13 959 358 918 different 0/1-equivalence classes of such polytopes. They form 5 850 402 014 combinatorial classes and 1 274 089 different f-vectors.…

组合数学 · 数学 2019-04-09 Aleksandr Maksimenko

It is known that polytopes with at most two nonsimple vertices are reconstructible from their graphs, and that $d$-polytopes with at most $d-2$ nonsimple vertices are reconstructible from their 2-skeletons. Here we close the gap between 2…

组合数学 · 数学 2018-11-28 Guillermo Pineda-Villavicencio , Julien Ugon , David Yost

The Monotone Upper Bound Problem (Klee, 1965) asks if the number M(d,n) of vertices in a monotone path along edges of a d-dimensional polytope with n facets can be as large as conceivably possible: Is M(d,n) = M_{ubt}(d,n), the maximal…

度量几何 · 数学 2009-09-29 Julian Pfeifle

A polytope in a finite-dimensional normed space is subequilateral if the length in the norm of each of its edges equals its diameter. Subequilateral polytopes occur in the study of two unrelated subjects: surface energy minimizing cones and…

度量几何 · 数学 2007-05-23 Konrad J Swanepoel

A cubical polytope is a polytope with all its facets being combinatorially equivalent to cubes. The paper is concerned with the linkedness of the graphs of cubical polytopes. A graph with at least $2k$ vertices is $k$-linked if, for every…

组合数学 · 数学 2019-09-30 Hoa Thi Bui , Guillermo Pineda-Villavicencio , Julien Ugon

Neighborly cubical polytopes exist: for any $n\ge d\ge 2r+2$, there is a cubical convex d-polytope $C^n_d$ whose $r$-skeleton is combinatorially equivalent to that of the $n$-dimensional cube. This solves a problem of Babson, Billera &…

组合数学 · 数学 2007-05-23 Michael Joswig , G"unter M. Ziegler

The problem of calculating exact lower bounds for the number of $k$-faces of $d$-polytopes with $n$ vertices, for each value of $k$, and characterising the minimisers, has recently been solved for $n\le2d$. We establish the corresponding…

组合数学 · 数学 2022-07-26 Guillermo Pineda-Villavicencio , David Yost

We prove that the number of vertices of a polytope of a particular kind is exponentially large in the dimension of the polytope. As a corollary, we prove that an n-dimensional centrally symmetric polytope with O(n) facets has 2^{Omega(n)}…

组合数学 · 数学 2012-04-24 Alexander Barvinok

Symmetric edge polytopes of graphs are important object in Ehrhart theory,and have an application to Kuramoto models. In the present paper, we study the upper and lower bounds for the number of facets of symmetric edge polytopes of…

组合数学 · 数学 2025-05-01 Aki Mori , Kenta Mori , Hidefumi Ohsugi
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