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Related papers: Examples and counterexamples in Ehrhart theory

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We show that the base polytope $P_M$ of any paving matroid $M$ can be systematically obtained from a hypersimplex by slicing off certain subpolytopes, namely base polytopes of lattice path matroids corresponding to panhandle-shaped Ferrers…

We determine lattice polytopes of smallest volume with a given number of interior lattice points. We show that the Ehrhart polynomials of those with one interior lattice point have largest roots with norm of order n^2, where n is the…

Metric Geometry · Mathematics 2007-05-23 Christian Bey , Martin Henk , Joerg M. Wills

Graph polytopes arising from vertex-weighted graphs were first introduced by B\'ona, Ju, and Yoshida. We prove a conjecture stating that for any simple connected graph, the numerator polynomial of the Ehrhart series of its graph polytope is…

Combinatorics · Mathematics 2026-04-13 Feihu Liu

Let M be a rational homology sphere plumbed 3-manifold associated with a connected negative definite plumbing graph. We show that its Seiberg-Witten invariants equal certain coefficients of an equivariant multivariable Ehrhart polynomial.…

Algebraic Geometry · Mathematics 2014-11-11 András Némethi , Tamás László

The order polytopes arising from the finite poset were first introduced and studied by Stanley. For any positive integer $d\geq 14$, Liu and Tsuchiya proved that there exists a non-Ehrhart positive order polytope of dimension $d$. They also…

Combinatorics · Mathematics 2026-04-13 Feihu Liu , Guoce Xin , Zihao Zhang

Many important problems in extremal combinatorics can be be stated as proving a pure binomial inequality in graph homomorphism numbers, i.e., proving that…

Combinatorics · Mathematics 2022-02-03 Grigoriy Blekherman , Annie Raymond

As shown by McMullen in 1983, the coefficients of the Ehrhart polynomial of a lattice polytope can be written as a weighted sum of facial volumes. The weights in such a local formula depend only on the outer normal cones of faces, but are…

Metric Geometry · Mathematics 2025-10-01 Maren H. Ring , Achill Schürmann

This article concerns the computational problem of counting the lattice points inside convex polytopes, when each point must be counted with a weight associated to it. We describe an efficient algorithm for computing the highest degree…

Combinatorics · Mathematics 2010-11-09 Velleda Baldoni , Nicole Berline , Jesús A. De Loera , Matthias Köppe , Michèle Vergne

In this paper, we give a formula for the number of lattice points in the dilations of Schubert matroid polytopes. As applications, we obtain the Ehrhart polynomials of uniform and minimal matroids as special cases, and give a recursive…

Combinatorics · Mathematics 2022-12-07 Neil J. Y. Fan , Yao Li

There is currently a growing interest in understanding which lattice simplices have unimodal local $h^\ast$-polynomials (sometimes called box polynomials); specifically in light of their potential applications to unimodality questions for…

Combinatorics · Mathematics 2020-01-14 Liam Solus

Quasi-period collapse occurs when the Ehrhart quasi-polynomial of a rational polytope has a quasi-period less than the denominator of that polytope. This phenomenon is poorly understood, and all known cases in which it occurs have been…

Combinatorics · Mathematics 2007-09-27 Christian Haase , Tyrrell B. McAllister

We give a survey on recent results on inequalities between the ranks of homotopy and cohomology groups (resp., graded components of mixed Hodge structures on these groups) of rationally elliptic spaces (resp., quasi-projective varieties…

Algebraic Topology · Mathematics 2023-06-27 Anatoly Libgober , Shoji Yokura

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

A generic orthotope is an orthogonal polytope whose tangent cones are described by read-once Boolean functions. The purpose of this note is to develop a theory ofEhrhart polynomials for integral generic orthotopes. The most remarkable part…

Combinatorics · Mathematics 2023-09-19 David Richter

In arXiv:1709.07504 Aguiar and Ardila give a Hopf monoid structure on hypergraphs as well as a general construction of polynomial invariants on Hopf monoids. Using these results, we define in this paper a new polynomial invariant on…

Combinatorics · Mathematics 2021-07-09 Jean-Christophe Aval , Théo Karaboghossian , Adrian Tanasa

We study the question of when 0-1 polytopes are normal or, equivalently, having the integer decomposition property. In particular, we shall associate to each 0-1 polytope a labeled hypergraph, and examine the equality between its Ehrhart…

Commutative Algebra · Mathematics 2014-09-08 Huy Tai Ha , Kuei-Nuan Lin

We determine the conditions for the existence of $C^p$-roots of curves of monic complex polynomials as well as for the existence of $C^p$-eigenvalues and $C^p$-eigenvectors of curves of normal complex matrices.

Classical Analysis and ODEs · Mathematics 2014-11-04 Armin Rainer

Using a ribbon structure of the graph, we construct a dissection of the symmetric edge polytope of a graph into unimodular simplices. Our dissection is shellable, and one can interpret the elements of the resulting $h$-vector via graph…

Combinatorics · Mathematics 2022-01-26 Tamás Kálmán , Lilla Tóthmérész

We reflect on the notions of positivity and square roots. We review many examples which underline our thesis that square roots of positive maps related to *-algebras are Hilbert modules. As a result of our considerations we discuss…

Operator Algebras · Mathematics 2017-08-23 Michael Skeide

For a convex polytope P with rational vertices, we count the number of integer points in integral dilates of P and its interior. The Ehrhart-Macdonald reciprocity law gives an intimate relation between these two counting functions. A…

Combinatorics · Mathematics 2007-05-23 Matthias Beck , Richard Ehrenborg