English
Related papers

Related papers: Roots of Ehrhart polynomials arising from graphs

200 papers

We construct a family of root-finding algorithms which exploit the branched covering structure of a polynomial of degree $d$ with a path-lifting algorithm for finding individual roots. In particular, the family includes an algorithm that…

Dynamical Systems · Mathematics 2025-10-20 Myong-Hi Kim , Scott Sutherland

We provide a formula for the Ehrhart polynomial of the connected matroid of size $n$ and rank $k$ with the least number of bases, also known as a minimal matroid. We prove that their polytopes are Ehrhart positive and $h^*$-real-rooted (and…

Combinatorics · Mathematics 2021-06-17 Luis Ferroni

A conjecture of Mihail and Vazirani states that the edge expansion of the graph of every $0/1$ polytope is at least one. Any lower bound on the edge expansion gives an upper bound for the mixing time of a random walk on the graph of the…

Combinatorics · Mathematics 2022-07-11 Brett Leroux , Luis Rademacher

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 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 prove that the Ehrhart polynomial of a zonotope is a specialization of the multiplicity Tutte polynomial. We derive some formulae for the volume and the number of integer points of the zonotope.

Combinatorics · Mathematics 2011-05-24 Michele D'Adderio , Luca Moci

Let $G$ be a simple graph and $I(G)$ be its edge ideal. In this article, we study the Castelnuovo-Mumford regularity of symbolic powers of edge ideals of join of graphs. As a consequence, we prove Minh's conjecture for wheel graphs,…

Commutative Algebra · Mathematics 2020-08-04 Arvind Kumar , Rajiv Kumar , Rajib Sarkar

In this paper we study the class of polytopes which can be obtained by taking the convex hull of some subset of the points $\{e_i-e_j \ \vert \ i \neq j\} \cup \{\pm e_i\}$ in $\mathbb{R}^n$, where $e_1,\dots,e_n$ is the standard basis of…

Combinatorics · Mathematics 2025-06-13 Konstanze Rietsch , Lauren Williams

We associate root polytopes to directed graphs and study them by using ribbon structures. Most attention is paid to what we call the semi-balanced case, i.e., when each cycle has the same number of edges pointing in the two directions.…

Combinatorics · Mathematics 2024-08-16 Tamás Kálmán , Lilla Tóthmérész

Adjacency polytopes, a.k.a. symmetric edge polytopes, associated with undirected graphs have been defined and studied in several seemingly independent areas including number theory, discrete geometry, and dynamical systems. In particular,…

Combinatorics · Mathematics 2020-07-15 Tianran Chen , Evgeniia Korchevskaia

The h^*-polynomial of a lattice polytope is the numerator of the generating function of the Ehrhart polynomial. Let P be a lattice polytope with h^*-polynomial of degree d and with linear coefficient h^*_1. We show that P has to be a…

Combinatorics · Mathematics 2008-09-29 Benjamin Nill

Given a family of lattice polytopes, two common questions in Ehrhart Theory are determining when a polytope has the integer decomposition property and determining when a polytope is reflexive. While these properties are of independent…

We give a method of generating strongly polynomial sequences of graphs, i.e., sequences $(H_{\mathbf{k}})$ indexed by a multivariate parameter $\mathbf{k}=(k_1,\ldots, k_h)$ such that, for each fixed graph $G$, there is a multivariate…

Combinatorics · Mathematics 2013-08-20 Delia Garijo , Andrew Goodall , Jaroslav Nesetril

The Ehrhart polynomial of a lattice polytope $P$ encodes information about the number of integer lattice points in positive integral dilates of $P$. The $h^\ast$-polynomial of $P$ is the numerator polynomial of the generating function of…

Combinatorics · Mathematics 2019-03-06 Matthias Beck , Katharina Jochemko , Emily McCullough

We study the root distribution of some univariate polynomials satisfying a recurrence of order two with linear and quadratic polynomial coefficients. We show that the set of non-isolated limits of zeros of the polynomials is the closure of…

Classical Analysis and ODEs · Mathematics 2020-03-02 David G. L. Wang , Jerry J. R. Zhang

In the last decade, the order polytope of the zigzag poset has been thoroughly studied. A related poset, called \emph{crown poset}, obtained by adding an extra relation between the endpoints of an even zigzag poset, is not so well…

Combinatorics · Mathematics 2025-12-10 Teemu Lundström , Leonardo Saud Maia Leite

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

In this article, we give two extended space formulations, respectively, for the induced tree and path polytopes of chordal graphs with vertex and edge variables. These formulations are obtained by proving that the induced tree and path…

Discrete Mathematics · Computer Science 2026-01-14 Alexandre Dupont-Bouillard

Given a pair of finite posets $A \subseteq P$, the function counting integer-valued order preserving extensions of an order preserving map $\lambda : A\rightarrow \mathbb{Z}$ from $A$ to $P$ is given by a piecewise polynomial in $\lambda$.…

Combinatorics · Mathematics 2026-04-20 Katharina Jochemko , Krishna Menon

As a generalization of the Edmonds arborescence packing theorem, Kamiyama--Katoh--Takizawa (2009) gave a good characterization of directed graphs that contain arc-disjoint arborescences spanning the set of vertices reachable from each root.…

Discrete Mathematics · Computer Science 2018-08-23 Tatsuya Matsuoka , Shin-ichi Tanigawa