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Related papers: The Sign Pattern Problem for Ehrhart Polynomials

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In Ehrhart theory, the well-known sign pattern problem asks: given a positive integer $d\geq 3$ and integers $1 \leq i_1 < \cdots < i_k \leq d-2$, does there exist a $d$-dimensional integral polytope $\mathcal{P}$ such that in its Ehrhart…

Combinatorics · Mathematics 2026-05-26 Feihu Liu , Sihao Tao , Guoce Xin

It is shown that, for each $d \geq 4$, there exists an integral convex polytope $\mathcal{P}$ of dimension $d$ such that each of the coefficients of $n, n^{2}, \ldots, n^{d-2}$ of its Ehrhart polynomial $i(\mathcal{P},n)$ is negative.…

Combinatorics · Mathematics 2016-05-03 Takayuki Hibi , Akihiro Higashitani , Akiyoshi Tsuchiya , Koutarou Yoshida

It is shown that, for each $d \geq 4$, there exists an integral convex polytope $\mathcal{P}$ of dimension $d$ such that each of the coefficients of $n, n^{2}, \ldots, n^{d-2}$ of its Ehrhart polynomial $i(\mathcal{P},n)$ is negative.

Combinatorics · Mathematics 2014-01-03 Takayuki Hibi , Akihiro Higashitani , Akiyoshi Tsuchiya , Koutarou Yoshida

The Ehrhart polynomial of a convex lattice polytope counts integer points in integral dilates of the polytope. We present new linear inequalities satisfied by the coefficients of Ehrhart polynomials and relate them to known inequalities. We…

Combinatorics · Mathematics 2007-05-23 M. Beck , J. A. De Loera , M. Develin , J. Pfeifle , R. P. Stanley

In this paper we are constructing integer lattice squares, cubes or hypercubes in $\mathbb R^d$ with $d\in \{2,3,4\}$. For squares and cubes we find a complete description of their Ehrhart polynomial. For hypercubes, we compute one of the…

Number Theory · Mathematics 2016-03-18 Eugen J. Ionascu

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

The notion of Ehrhart tensor polynomials, a natural generalization of the Ehrhart polynomial of a lattice polytope, was recently introduced by Ludwig and Silverstein. We initiate a study of their coefficients. In the vector and matrix…

Combinatorics · Mathematics 2017-06-07 Sören Berg , Katharina Jochemko , Laura Silverstein

The Ehrhart polynomial of an integral convex polytope counts the number of lattice points in dilates of the polytope. In math.CO/0402148, the authors conjectured that for any cyclic polytope with integral parameters, the Ehrhart polynomial…

Combinatorics · Mathematics 2007-05-23 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…

Combinatorics · Mathematics 2025-12-10 Krishna Menon , Emil Verkama

In this paper we calculate the Ehrhart's polynomial associated with a 2-dimensional regular polytope (i.e. equilateral triangles) in $\mathbb Z^3$. The polynomial takes a relatively simple form in terms of the coordinates of the vertices of…

Number Theory · Mathematics 2011-07-12 Eugen J. Ionascu

We say a polytope is Ehrhart positive if all the coefficients in its Ehrhart polynomial are positive. Answering an Ehrhart positivity question posed on Mathoverflow, Stanley provided an example of a non-Ehrhart-positive order polytope of…

Combinatorics · Mathematics 2020-09-08 Fu Liu , Akiyoshi Tsuchiya

Several polytopes arise from finite graphs. For edge and symmetric edge polytopes, in particular, exhaustive computation of the Ehrhart polynomials not merely supports the conjecture of Beck {\it et al.}\ that all roots $\alpha$ of Ehrhart…

Combinatorics · Mathematics 2015-03-13 Tetsushi Matsui , Akihiro Higashitani , Yuuki Nagazawa , Hidefumi Ohsugi , Takayuki Hibi

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

A polytope is integral if all of its vertices are lattice points. The constant term of the Ehrhart polynomial of an integral polytope is known to be 1. In previous work, we showed that the coefficients of the Ehrhart polynomial of a…

Combinatorics · Mathematics 2009-11-12 Fu Liu

For an integral convex polytope $\mathcal{P} \subset \mathbb{R}^d$, we recall $L_\mathcal{P}(n)=|n\mathcal{P} \cap \mathbb{Z}^d|$ the Ehrhart polynomial of $\mathcal{P}$. Let $g_r(\mathcal{P})$ be the $r$th coefficients of…

Combinatorics · Mathematics 2020-09-08 Akiyoshi Tsuchiya

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

Over a decade ago De Loera, Haws and K\"oppe conjectured that Ehrhart polynomials of matroid polytopes have only positive coefficients and that the coefficients of the corresponding $h^*$-polynomials form a unimodal sequence. The first of…

Combinatorics · Mathematics 2022-08-05 Luis Ferroni , Katharina Jochemko , Benjamin Schröter

Ehrhart discovered that the function that counts the number of lattice points in dilations of an integral polytope is a polynomial. We call the coefficients of this polynomial Ehrhart coefficients, and say a polytope is Ehrhart positive if…

Combinatorics · Mathematics 2018-09-05 Fu Liu

It is already known that order polytopes and chain polytopes are always 2-level polytopes. In general, this is not true for marked order and marked chain polytopes. We study the geometry of marked order polytopes, marked chain polytopes,…

Combinatorics · Mathematics 2025-03-26 Jan Stricker

We consider three realization problems about monic real univariate polynomials without vanishing coefficients. Such a polynomial $P:=\sum_{j=0}^db_jx^j$ defines the sign pattern $\sigma (P):=({\rm sgn}(b_d)$, $\ldots$, ${\rm sgn}(b_0))$.…

Classical Analysis and ODEs · Mathematics 2026-01-16 Vladimir Petrov Kostov
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