中文
相关论文

相关论文: Explicit Construction of Polytopes whose Ehrhart P…

200 篇论文

For positive integers $m$ and $n$, the partial permutohedron $\mathcal{P}(m,n)$ is a certain integral polytope in $\mathbb{R}^m$, which can be defined as the convex hull of the vectors from $\{0,1,\ldots,n\}^m$ whose nonzero entries are…

组合数学 · 数学 2024-03-12 Roger E. Behrend

It is proved that a certain symmetric sequence of nonnegative integers arising in the enumeration of magic squares of given size n by row sums or, equivalently, in the generating function of the Ehrhart polynomial of the polytope of doubly…

组合数学 · 数学 2007-05-23 Christos A. Athanasiadis

We give partial generalizations of the classical Descartes' rule of signs to multivariate polynomials (with real exponents), in the sense that we provide upper bounds on the number of connected components of the complement of a hypersurface…

代数几何 · 数学 2022-07-07 Elisenda Feliu , Máté L. Telek

In earlier work in collaboration with Pavel Galashin and Thomas McConville we introduced a version of chip-firing for root systems. Our investigation of root system chip-firing led us to define certain polynomials analogous to Ehrhart…

组合数学 · 数学 2019-12-24 Sam Hopkins , Alexander Postnikov

A well-known theorem of Quillen says that if $r(z,\bar{z})$ is a bihomogeneous polynomial on ${\mathbb{C}}^n$ positive on the sphere, then there exists $d$ such that $r(z,\bar{z}){\lVert z \rVert}^{2d}$ is a squared norm. We obtain…

代数几何 · 数学 2013-12-05 Jennifer Halfpap , Jiri Lebl

Bosse et al. conjectured that for every natural number $d \ge 2$ and every $d$-dimensional polytope $P$ in $\real^d$ there exist $d$ polynomials $p_0(x),...,p_{d-1}(x)$ satisfying $P=\{x \in \mathbb{R}^d : p_0(x) \ge 0, >..., p_{d-1}(x) \ge…

度量几何 · 数学 2008-07-15 Gennadiy Averkov , Martin Henk

We give a combinatorial formula for the Ehrhart coefficients of a certain class of weighted multi-hypersimplices. In a special case, where these polytopes coincide with the base polytope of the panhandle matroid $\textrm{Pan}_{k,n-2,n}$, we…

组合数学 · 数学 2023-12-13 Daniel McGinnis

For an $n$-dimensional lattice simplex $\Delta_{(1,\mathbf{q})}$ with vertices given by the standard basis vectors and $-\mathbf{q}$ where $\mathbf{q}$ has positive entries, we investigate when the Ehrhart $h^*$-polynomial for…

组合数学 · 数学 2018-07-20 Benjamin Braun , Fu Liu

It is known that the Ehrhart polynomials of cross-polytopes, as well as of pyramids over them, have positive coefficients. We give a combinatorial proof of this fact by showing that a scaled version of the Ehrhart polynomials are generating…

组合数学 · 数学 2025-12-10 Krishna Menon , Emil Verkama

The local $h^*$-polynomial is a natural invariant of a lattice polytope appearing in Ehrhart theory and Hodge theory. In this work, we study the question posed in [GKZ94] concerning the classification of lattice simplices with vanishing…

组合数学 · 数学 2025-12-23 Vadym Kurylenko

We conduct a systematic study of the Ehrhart theory of certain slices of rectangular prisms. Our polytopes are generalizations of the hypersimplex and are contained in the larger class of polypositroids introduced by Lam and Postnikov;…

组合数学 · 数学 2025-04-30 Luis Ferroni , Daniel McGinnis

We generalize R. P. Stanley's celebrated theorem that the $h^\ast$-polynomial of the Ehrhart series of a rational polytope has nonnegative coefficients and is monotone under containment of polytopes. We show that these results continue to…

The classical Descartes' rule of signs limits the number of positive roots of a real polynomial in one variable by the number of sign changes in the sequence of its coefficients. One can ask the question which pairs of nonnegative integers…

经典分析与常微分方程 · 数学 2019-05-10 Vladimir Petrov Kostov

It was observed by Bump et al. that Ehrhart polynomials in a special family exhibit properties similar to the Riemann {\zeta} function. The construction was generalized by Matsui et al. to a larger family of reflexive polytopes coming from…

组合数学 · 数学 2018-04-20 Akihiro Higashitani , Mario Kummer , Mateusz Michałek

In Ehrhart theory, the $h^*$-vector of a rational polytope often provide insights into properties of the polytope that may be otherwise obscured. As an example, the Birkhoff polytope, also known as the polytope of real doubly-stochastic…

组合数学 · 数学 2015-04-28 Robert Davis

A subset $S$ of vertices of a graph $G$ is called a perfectly matchable set of $G$ if the subgraph induced by $S$ contains a perfect matching. The perfectly matchable set polynomial of $G$, first made explicit by Ohsugi and Tsuchiya, is the…

组合数学 · 数学 2022-08-01 Robert Davis , Florian Kohl

For a real degree $d$ polynomial $P$ with all nonvanishing coefficients, with $c$ sign changes and $p$ sign preservations in the sequence of its coefficients ($c+p=d$), Descartes' rule of signs says that $P$ has $pos\leq c$ positive and…

经典分析与常微分方程 · 数学 2020-12-09 Hassen Cheriha , Yousra Gati , Vladimir Petrov Kostov

We use the ordinary Euler operator to compute the Ehrhart series for an arbitrary lattice polytope. The resulting formula involves the coefficients of the Ehrhart polynomial, combined via Eulerian numbers. We use this to compute $h^*_{d-1}$…

组合数学 · 数学 2023-03-31 Wayne A. Johnson

We consider a formula of Stanley that expresses the Ehrhart generating polynomial of a polyhedral complex in terms of the h-polynomials of toric varieties. We prove that the coefficients in this expression are all non-negative and show that…

代数几何 · 数学 2007-05-23 Kalle Karu

We present a polynomial time algorithm to compute any fixed number of the highest coefficients of the Ehrhart quasi-polynomial of a rational simplex. Previously such algorithms were known for integer simplices and for rational polytopes of…

组合数学 · 数学 2007-05-23 Alexander Barvinok