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Related papers: Ehrhart positivity for lattice path matroids

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Demazure characters, also known as key polynomials, generalize the classical Schur polynomials. In particular, when all variables are set equal to $1$, these polynomials count the number of integer points in a certain class of…

Combinatorics · Mathematics 2023-11-14 Per Alexandersson , Elie Alhajjar

Consideration of a question of E. R. Berlekamp led Carlitz, Roselle, and Scoville to give a combinatorial interpretation of the entries of certain matrices of determinant~1 in terms of lattice paths. Here we generalize this result by…

Combinatorics · Mathematics 2014-04-21 Christine Bessenrodt , Richard P. Stanley

We initiate the study of a type $C_n$ generalization of the lattice path matroids defined by Bonin, de Mier, and Noy. These are delta matroids whose feasible sets are in bijection with lattice paths which are symmetric along the main…

Combinatorics · Mathematics 2023-11-28 Douglas M. Chen , Mario Sanchez , John Veliz , Zhiyan Ying

We prove the complete monotonicity on $(0,\infty)^n$ for suitable inverse powers of the spanning-tree polynomials of graphs and, more generally, of the basis generating polynomials of certain classes of matroids. This generalizes a result…

Combinatorics · Mathematics 2014-12-04 Alexander D. Scott , Alan D. Sokal

In $1980$ White conjectured that every element of the toric ideal of a matroid is generated by quadratic binomials corresponding to symmetric exchanges. We prove White's conjecture for high degrees with respect to the rank. This extends our…

Combinatorics · Mathematics 2021-12-01 Michał Lasoń

A fundamental theorem of matroid theory establishes that a transversal matroid is representable over fields of any characteristic. It was proved in 1970 by Piff and Welsh: their proof is elegant and concise and, moveover, constructive.…

Combinatorics · Mathematics 2017-07-24 Carrie Rutherford , Robin Whitty

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

Ismail et al. (Constr. Approx. {\bf 15} (1999) 69--81) proved the positivity of some trigonometric polynomials with single binomial coefficients. In this paper, we prove some similar results by replacing the binomial coefficients with…

Combinatorics · Mathematics 2011-03-25 Victor J. W. Guo , Jiang Zeng

Ferroni and Larson gave a combinatorial interpretation of the braid Kazhdan-Lusztig polynomials in terms of series-parallel matroids. As a consequence, they confirmed an explicit formula for the leading Kazhdan-Lusztig coefficients of braid…

Combinatorics · Mathematics 2023-11-14 Alice L. L. Gao , Nicholas Proudfoot , Arthur L. B. Yang , Zhong-Xue Zhang

Multimatroids generalize matroids, delta-matroids, and isotropic systems, and transition polynomials of multimatroids subsume various polynomials for these latter combinatorial structures, such as the interlace polynomial and the…

Combinatorics · Mathematics 2017-08-18 Robert Brijder

Stanley has conjectured that the h-vector of a matroid complex is a pure O-sequence. We will prove this for cotransversal matroids by using generalized permutohedra. We construct a bijection between lattice points inside a r-dimensional…

Combinatorics · Mathematics 2012-10-04 SuHo Oh

Lattice paths called $\ell$-Schr\"oder paths are introduced. They are paths on the upper half-plane consisting of $\ell+2$ types of steps: $(i,\ell-i)$ for $i=0,\ldots,\ell$, and $(1,-1)$. Those paths generalize Schr\"oder paths and some…

Combinatorics · Mathematics 2023-10-17 Mawo Ito

Using the integral representations of the solutions of Schr\"odinger equation, which are the essential ingredients of the Gel'fand-Levitan and Marchenko integral equations of inverse scattering theory, we obtain a general theorem on the…

Mathematical Physics · Physics 2007-06-28 Khosrow Chadan

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…

Using a known recursive formula for the Grothendieck classes of the moduli spaces $\overline{\mathcal M}_{0,n}$, we prove that they satisfy an asymptotic form of ultra-log-concavity as polynomials in the Lefschetz class. We also observe…

Algebraic Geometry · Mathematics 2024-02-09 Paolo Aluffi , Stephanie Chen , Matilde Marcolli

An outstanding conjecture on roots of Ehrhart polynomials says that all roots $\alpha$ of the Ehrhart polynomial of an integral convex polytope of dimension $d$ satisfy $-d \leq \Re(\alpha) \leq d-1$. In this paper, we suggest some…

Combinatorics · Mathematics 2011-06-29 Akihiro Higashitani

In this note, simple proofs of certain well-known results involving the positive square root of positive matrices are given.

General Mathematics · Mathematics 2023-06-21 Mohamed Amine Aouichaoui , Mohammed Hichem Mortad

The Chow polynomial of a matroid is a fundamental invariant whose coefficients exhibit strong positivity properties, including $\gamma$-positivity. We interpret the normalized Chow coefficients as a probability distribution and establish…

Combinatorics · Mathematics 2026-04-30 Ronnie Cheng , Wangyang Lin

We begin with a review of Tutte's homotopy theory, which concerns the structure of certain graph associated to a matroid (together with some extra data). Concretely, Tutte's path theorem asserts that this graph is connected, and his…

Combinatorics · Mathematics 2026-01-21 Matthew Baker , Tong Jin , Oliver Lorscheid

We focus on checking the validity of the half-plane property on two prominent classes of transversal matroids, namely lattice path matroids and bicircular matroids. We show that lattice path matroids satisfy the half-plane property.…

Combinatorics · Mathematics 2024-02-12 Ayush Kumar Tewari
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