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Related papers: Lattice Path Matroid Polytopes

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This paper is a continuation of my paper "Lattices of flats for symplectic matroids". We explore geometric constructions originating from the lattice of flats of ranked symplectic matroids. We observe that a ranked symplectic matroid always…

Combinatorics · Mathematics 2026-01-08 Or Raz

It is well known that a matroid L is a lift of a matroid M if and only if every circuit of L is the union of some circuits of M. In this paper we give a simpler proof of this important theorem. We also described a discrete homotopy theorem…

Combinatorics · Mathematics 2022-10-03 Jose De Jesus , Alexander Kelmans

We introduce the notion of lattice path matroidal subdivisions, or LPM subdivisions for short, and show that these subdivisions are regular and hence the weight vectors for them lie in the Dressian. This leads us to explore the structure of…

Combinatorics · Mathematics 2023-07-11 Ayush Kumar Tewari , Ahmed Umer Ashraf

Covering-based rough set theory is a useful tool to deal with inexact, uncertain or vague knowledge in information systems. Geometric lattice has widely used in diverse fields, especially search algorithm design which plays important role…

Artificial Intelligence · Computer Science 2012-10-02 Aiping Huang , William Zhu

$q$-Matroids are defined on complemented modular support lattices. Minors of length 2 are of four types as in a "classical" matroid. Tutte polynomials $\tau(x,y)$ of matroids are calculated either by recursion over deletion/contraction of…

Combinatorics · Mathematics 2017-07-13 Guus Bollen , Henry Crapo , Relinde Jurrius

Let M to be a matroid defined on a finite set E. A subset L of E is locked in M if L is 2-connected in M, the complement of L is 2-connected in the dual M*, and min{r(L), r*(complement of L)} is greater than 1. In this paper, we prove that…

Combinatorics · Mathematics 2016-12-22 Brahim Chaourar

We prove that all lattice path matroids are Ehrhart positive. This unifies and generalizes numerous results on the Ehrhart positivity of matroids developed over the last two decades. We rely on our previous work on the positivity of order…

Combinatorics · Mathematics 2026-05-22 Luis Ferroni , Alejandro H. Morales , Greta Panova

In this paper, we enumerate lattice paths with certain constraints and apply the corresponding results to develop formulas for calculating the dimensions of submodules of a class of modules for planar upper triangular rook monoids. In…

Combinatorics · Mathematics 2017-08-24 Jianqiang Feng , Wenli Liu , Ximei Bai , Zhenheng Li

We prove that the extension complexity of the independence polytope of every regular matroid on $n$ elements is $O(n^6)$. Past results of Wong and Martin on extended formulations of the spanning tree polytope of a graph imply a $O(n^2)$…

Combinatorics · Mathematics 2019-12-23 Manuel Aprile , Samuel Fiorini

We introduce a new type of lattice path, called brick-wall lattice path, and we derive a formula which counts the number of paths on these lattices imposing certain restrictions on the Cartesian plane. Connections to the Fibonacci sequence,…

Combinatorics · Mathematics 2018-04-17 Leonard Daus , Valeriu Beiu , Simon Cowell , Philippe Poulin

We characterize the polytopes in $\mathbb{R}^d$ (not necessarily convex or connected ones) which multi-tile the space by translations along a given lattice. We also give a necessary and sufficient condition for two polytopes in…

Combinatorics · Mathematics 2019-10-30 Nir Lev , Bochen Liu

A positroid is a special case of a realizable matroid that arose from the study of the totally nonnegative part of the Grassmannian by Postnikov. In this paper, we study the facets of its matroid polytope and the independent set polytope.…

Combinatorics · Mathematics 2021-08-17 Suho Oh , David Xiang

The concept of a matroid quotient has connections to fundamental questions in the geometry of flag varieties. In previous work, Benedetti and Knauer characterized quotients in the class of lattice path matroids (LPMs) in terms of a simple…

Combinatorics · Mathematics 2025-04-11 Carolina Benedetti , Anton Dochtermann , Kolja Knauer , Yupeng Li

We give an explicit description of the poset of cells of Bergman complexes of Lattice Path Matroids and establish a criterion for its simpliciality, in terms of the shape of the bounding paths.

Combinatorics · Mathematics 2015-08-21 Emanuele Delucchi , Martin Dlugosch

We present a simple proof of the fact that the base (and independence) polytope of a rank $n$ regular matroid over $m$ elements has an extension complexity $O(mn)$.

Discrete Mathematics · Computer Science 2017-02-08 Rohit Gurjar , Nisheeth K. Vishnoi

A lattice polytope is called spanning if its lattice points affinely span the ambient lattice. We show as a corollary to a general result in the Ehrhart theory of lattice polytopes that the $h^*$-vector of a spanning lattice polytope has no…

Combinatorics · Mathematics 2019-10-25 Johannes Hofscheier , Lukas Katthän , Benjamin Nill

Let $\mathcal{P} \subset \mathbb{R}^d$ be a lattice polytope of dimension $d$. Let $b(\mathcal{P})$ denote the number of lattice points belonging to the boundary of $\mathcal{P}$ and $c(\mathcal{P})$ that to the interior of $\mathcal{P}$.…

Combinatorics · Mathematics 2024-11-12 Ginji Hamano , Ichiro Sainose , Takayuki Hibi

A transportation polytope consists of all multidimensional arrays or tables of non-negative real numbers that satisfy certain sum conditions on subsets of the entries. They arise naturally in optimization and statistics, and also have…

Combinatorics · Mathematics 2013-07-02 Jesús A. De Loera , Edward D. Kim

We are interested in expanding our understanding of symplectic matroids by exploring the properties of a class of symplectic matroids with a "lattice of flats". Taking a well-behaved family of subdivisions of the cross polytope we obtain a…

Combinatorics · Mathematics 2026-01-08 Or Raz

Let ${\cal PO}_n$ be the semigroup of all order-preserving partial transformations of a finite chain. It is shown that there exist bijections between the set of certain lattice paths in the Cartesian plane that start at $(0,0)$, end at…

Combinatorics · Mathematics 2013-04-30 A. Laradji , A. Umar
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