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20192023
most citedMatroids are not Ehrhart positive

22 citations · 134 across the 13 of their papers we have counts for

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13 papers

math.CO2023

Examples and counterexamples in Ehrhart theory

Luis Ferroni, Akihiro Higashitani

This article provides a comprehensive exposition about inequalities that the coefficients of Ehrhart polynomials and -polynomials satisfy under various assumptions. We pay par…

math.CO2023★ 5 cited

Kazhdan-Lusztig polynomials of braid matroids

Luis Ferroni, Matt Larson

We provide a combinatorial interpretation of the Kazhdan--Lusztig polynomial of the matroid arising from the braid arrangement of type , which gives an interpreta…

math.CO2022★ 14 cited

Hilbert-Poincaré series of matroid Chow rings and intersection cohomology

Luis Ferroni, Jacob P. Matherne, Matthew Stevens +1

We study the Hilbert series of four objects arising in the Chow-theoretic and Kazhdan-Lusztig framework of matroids. These are, respectively, the Hilbert series of the Chow ring, t…

math.CO2022★ 15 cited

Valuative invariants for large classes of matroids

Luis Ferroni, Benjamin Schröter

We study an operation in matroid theory that allows one to transition a given matroid into another with more bases via relaxing a \emph{stressed subset}. This framework provides a…

math.CO2022★ 3 cited

The Merino--Welsh conjecture for split matroids

Luis Ferroni, Benjamin Schröter

In 1999 Merino and Welsh conjectured that evaluations of the Tutte polynomial of a graph satisfy an inequality. In this short article we show that the conjecture generalized to mat…

math.CO2022★ 2 cited

Lattice points in slices of prisms

Luis Ferroni, Daniel McGinnis

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 c…

math.CO2021★ 14 cited

Stressed hyperplanes and Kazhdan-Lusztig gamma-positivity for matroids

Luis Ferroni, George D. Nasr, Lorenzo Vecchi

In this article we make several contributions of independent interest. First, we introduce the notion of stressed hyperplane of a matroid, essentially a type of cyclic flat that pe…

math.CO2021★ 11 cited

Ehrhart polynomials of rank two matroids

Luis Ferroni, Katharina Jochemko, Benjamin Schröter

Over a decade ago De Loera, Haws and Köppe conjectured that Ehrhart polynomials of matroid polytopes have only positive coefficients and that the coefficients of the corresponding…

math.CO2021★ 22 cited

Matroids are not Ehrhart positive

Luis Ferroni

In this article we disprove the conjectures asserting the positivity of the coefficients of the Ehrhart polynomial of matroid polytopes by De Loera, Haws and Köppe (2007) and of ge…

math.CO2021★ 11 cited

Matroid relaxations and Kazhdan-Lusztig non-degeneracy

Luis Ferroni, Lorenzo Vecchi

In this paper we study the interplay between the operation of circuit-hyperplane relaxation and the Kazhdan--Lusztig theory of matroids. We obtain a family of polynomials, not depe…

math.CO2020★ 3 cited

Integer point enumeration on independence polytopes and half-open hypersimplices

Luis Ferroni

In this paper we investigate the Ehrhart Theory of the independence matroid polytope of uniform matroids. It is proved that these polytopes have an Ehrhart polynomial with positive…

math.CO2020★ 19 cited

On the Ehrhart Polynomial of Minimal Matroids

Luis Ferroni

We provide a formula for the Ehrhart polynomial of the connected matroid of size and rank with the least number of bases, also known as a minimal matroid. We prove that the…

math.CO2019★ 15 cited

Hypersimplices are Ehrhart Positive

Luis Ferroni

We consider the Ehrhart polynomial of hypersimplices. It is proved that these polynomials have positive coefficients and we give a combinatorial formula for each of them. This sett…