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Related papers: Ehrhart polynomials of lattice-face polytopes

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Blind and Mani, and later Kalai, showed that the face lattice of a simple polytope is determined by its graph, namely its $1$-skeleton. Call a vertex of a $d$-polytope \emph{nonsimple} if the number of edges incident to it is more than $d$.…

Combinatorics · Mathematics 2018-03-16 Joseph Doolittle , Eran Nevo , Guillermo Pineda-Villavicencio , Julien Ugon , David Yost

Equivariant Ehrhart theory enumerates the lattice points in a polytope with respect to a group action. Answering a question of Stapledon, we describe the equivariant Ehrhart theory of the permutahedron, and we prove his Effectiveness…

Combinatorics · Mathematics 2020-07-20 Federico Ardila , Mariel Supina , Andrés R. Vindas-Meléndez

We study the Ehrhart theory of quadratic irrational polytopes that undergo vector dilations. That is, for a given polytope with vertices in $\mathbb{Q}(\sqrt{D})$, and a different dilation factor for each facet, we show that the leading…

Number Theory · Mathematics 2018-10-03 Yashaswika Gaur , Tian An Wong

We obtain a recurrence relation for the f-polynomial of Gelfand-Zetlin polytopes by analyzing geometric properties of a linear projection of the Gelfand-Zetlin polytope onto a cube. We apply this recurrence relation to find explicit…

Combinatorics · Mathematics 2025-07-21 Ekaterina V. Melikhova

The univariate Ehrhart and $h^*$-polynomials of lattice polytopes have been widely studied. We describe methods from toric geometry for computing multivariate versions of volume, Ehrhart and $h^*$-polynomials of lattice polytropes, which…

Combinatorics · Mathematics 2023-03-08 Marie-Charlotte Brandenburg , Sophia Elia , Leon Zhang

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…

Combinatorics · Mathematics 2023-12-13 Daniel McGinnis

The n'th Birkhoff polytope is the set of all doubly stochastic n-by-n matrices, that is, those matrices with nonnegative real coefficients in which every row and column sums to one. A wide open problem concerns the volumes of these…

Combinatorics · Mathematics 2007-05-23 Matthias Beck , Dennis Pixton

Given a real closed polytope $P$, we first describe the Fourier transform of its indicator function by using iterations of Stokes' theorem. We then use the ensuing Fourier transform formulations, together with the Poisson summation formula,…

Combinatorics · Mathematics 2018-08-02 Ricardo Diaz , Quang-Nhat Le , Sinai Robins

Hypersimplices are well-studied objects in combinatorics, optimization, and representation theory. For each hypersimplex, we define a new family of subpolytopes, called r-stable hypersimplices, and show that a well-known regular unimodular…

Combinatorics · Mathematics 2016-03-17 Benjamin Braun , Liam Solus

Faces play a central role in the combinatorial and computational aspects of polyhedra. In this paper, we present the first formalization of faces of polyhedra in the proof assistant Coq. This builds on the formalization of a library…

Logic in Computer Science · Computer Science 2023-06-22 Xavier Allamigeon , Ricardo D. Katz , Pierre-Yves Strub

The Ehrhart polynomial $ehr_P (n)$ of a lattice polytope $P$ gives the number of integer lattice points in the $n$-th dilate of $P$ for all integers $n\geq 0$. The degree of $P$ is defined as the degree of its $h^\ast$-polynomial, a…

Combinatorics · Mathematics 2024-09-24 Matthias Beck , Ellinor Janssen , Katharina Jochemko

This paper proposes a novel and simple algorithm of facet enumeration for convex polytopes. The complexity of the algorithm is discussed. The algorithm is implemented in Matlab. Some simple polytopes with known H-representations and…

Optimization and Control · Mathematics 2025-01-23 Yaguang Yang

The local $h^*$-polynomial of a lattice polytope is an important invariant arising in Ehrhart theory. Our focus is on lattice simplices presented in Hermite normal form with a single non-trivial row. We prove that when the off-diagonal…

The aim of the paper is to calculate face numbers of simple generalized permutohedra, and study their f-, h- and gamma-vectors. These polytopes include permutohedra, associahedra, graph-associahedra, simple graphic zonotopes, nestohedra,…

Combinatorics · Mathematics 2007-05-23 Alexander Postnikov , Victor Reiner , Lauren Williams

We investigate properties of Ehrhart polynomials for matroid polytopes, independence matroid polytopes, and polymatroids. In the first half of the paper we prove that for fixed rank their Ehrhart polynomials are computable in polynomial…

Combinatorics · Mathematics 2017-01-03 Jesús A. De Loera , David C. Haws , Matthias Köppe

Ehrhart polynomials are extensively-studied structures that interpolate the discrete volume of the dilations of integral $n$-polytopes. The coefficients of Ehrhart polynomials, however, are still not fully understood, and it is not known…

Combinatorics · Mathematics 2021-01-22 Fiona Abney-McPeek , Sanket Biswas , Senjuti Dutta , Yongyuan Huang , Deyuan Li , Nancy Xu

We give novel and explicit formulas for the Ehrhart quasi-polynomials of rational simple polytopes, in terms of Barnes polynomials and discrete moments of half-open parallelepipeds. These formulas also hold for all positive dilations of a…

Combinatorics · Mathematics 2026-02-02 Sinai Robins

Let $\mathcal{P} \subset \mathbb{R}^d$ be a lattice polytope of dimension $d$. Let $b(\mathcal{P})$ denote the number of lattice points belonging to the boundary of $\mathcal{P}$ and $c(\mathcal{P})$ that to the interior of $\mathcal{P}$.…

Combinatorics · Mathematics 2024-11-12 Ginji Hamano , Ichiro Sainose , Takayuki Hibi

We show how to compute the Ehrhart polynomial of the free sum of two lattice polytopes containing the origin $P$ and $Q$ in terms of the enumerative combinatorics of $P$ and $Q$. This generalizes work of Beck, Jayawant, McAllister, and…

Combinatorics · Mathematics 2021-10-05 Alan Stapledon

For any lattice polytope $P$, we consider an associated polynomial $\bar{\delta}_{P}(t)$ and describe its decomposition into a sum of two polynomials satisfying certain symmetry conditions. As a consequence, we improve upon known…

Combinatorics · Mathematics 2009-09-24 Alan Stapledon