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Related papers: Face enumeration for split matroid polytopes

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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

We obtain a recurrence relation for the f-polynomial of Gelfand-Zetlin polytopes by analyzing geometric properties of a linear projection of the Gelfand-Zetlin polytope onto a cube. We apply this recurrence relation to find explicit…

Combinatorics · Mathematics 2025-07-21 Ekaterina V. Melikhova

A class of matroids is introduced which is very large as it strictly contains all paving matroids as special cases. As their key feature these split matroids can be studied via techniques from polyhedral geometry. It turns out that the…

Combinatorics · Mathematics 2018-07-02 Michael Joswig , Benjamin Schröter

We discuss several extension properties of matroids and polymatroids and their application as necessary conditions for the existence of different matroid representations, namely linear, folded linear, algebraic, and entropic…

Combinatorics · Mathematics 2025-02-24 Michael Bamiloshin , Oriol Farràs , Carles Padró

The aim of the paper is to calculate face numbers of simple generalized permutohedra, and study their f-, h- and gamma-vectors. These polytopes include permutohedra, associahedra, graph-associahedra, simple graphic zonotopes, nestohedra,…

Combinatorics · Mathematics 2007-05-23 Alexander Postnikov , Victor Reiner , Lauren Williams

This is a continuation of the early paper concerning matroid base polytope decomposition. Here, we will present sufficient conditions on $M$ so its base matroid polytope $P(M)$ has a {\em sequence} of hyperplane splits. The latter yields to…

Combinatorics · Mathematics 2013-11-28 Vanessa Chatelain , Jorge Ramirez Alfonsin

Fix two lattice paths $P$ and $Q$ from $(0,0)$ to $(m,r)$ that use East and North steps with $P $ never going above $Q$. Bonin et al. show that the lattice paths that go from $(0,0)$ to $(m,r)$ and remain bounded by $P$ and $Q$ can be…

Combinatorics · Mathematics 2012-12-27 Hoda Bidkhori

We study paving matroids, their realization spaces, and their closures, along with matroid varieties and circuit varieties. Within this context, we introduce three distinct methods for generating polynomials within the associated ideals of…

Algebraic Geometry · Mathematics 2026-03-24 Emiliano Liwski , Fatemeh Mohammadi

A basic combinatorial invariant of a convex polytope $P$ is its $f$-vector $f(P)=(f_0,f_1,\dots,f_{\dim P-1})$, where $f_i$ is the number of $i$-dimensional faces of $P$. Steinitz characterized all possible $f$-vectors of $3$-polytopes and…

Combinatorics · Mathematics 2018-08-13 Takuya Kusunoki , Satoshi Murai

Closed-form generating functions for counting one-face rooted hypermaps with a known number of darts by number of vertices and edges is found, using matrix integral expressions relating to the reduced density operator of a bipartite quantum…

Combinatorics · Mathematics 2015-01-28 Jacob P. Dyer

In this work we present an algorithm to construct sparse-paving matroids over finite set $S$. From this algorithm we derive some useful bounds on the cardinality of the set of circuits of any Sparse-Paving matroids which allow us to prove…

Combinatorics · Mathematics 2018-10-18 B. Mederos , M. Takane , G. Tapia-Sanchez , B. Zavala

We investigate the combinatorics and geometry of permutation polytopes associated to cyclic permutation groups, i.e., the convex hulls of cyclic groups of permutation matrices. We give formulas for their dimension and vertex degree. In the…

Combinatorics · Mathematics 2011-09-02 Barbara Baumeister , Christian Haase , Benjamin Nill , Andreas Paffenholz

This dissertation presents new results on three different themes all related to matroid polytopes. First we investigate properties of Ehrhart polynomials of matroid polytopes, independence matroid polytopes, and polymatroids. We prove that…

Combinatorics · Mathematics 2009-05-28 David C. Haws

Matroids give rise to several natural constructions of polytopes. Inspired by this, we examine polytopes that arise from the signed circuits of an oriented matroid. We give the dimensions of these polytopes arising from graphical oriented…

Combinatorics · Mathematics 2025-01-03 Laura Escobar , Jodi McWhirter

We discuss a new memory-efficient depth-first algorithm and its implementation that iterates over all elements of a finite locally branched lattice. This algorithm can be applied to face lattices of polyhedra and to various generalizations…

Combinatorics · Mathematics 2022-03-28 Jonathan Kliem , Christian Stump

We discuss the problem of counting vertices in Gelfand-Zetlin polytopes. Namely, we deduce a partial differential equation with constant coefficients on the exponential generating function for these numbers. For some particular classes of…

Combinatorics · Mathematics 2014-06-06 Pavel Gusev , Valentina Kiritchenko , Vladlen Timorin

In this paper we investigate the number of integer points lying in dilations of lattice path matroid polytopes. We give a characterization of such points as polygonal paths in the diagram of the lattice path matroid. Furthermore, we prove…

Combinatorics · Mathematics 2017-10-26 Kolja Knauer , Leonardo Martínez-Sandoval , Jorge Luis Ramírez Alfonsín

Split matroids form a minor-closed class of matroids, and are defined by placing conditions on the system of split hyperplanes in the matroid base polytope. They can equivalently be defined in terms of structural properties involving cyclic…

Combinatorics · Mathematics 2021-01-07 Amanda Cameron , Dillon Mayhew

We compare various viewpoints on down-sets (simplicial complexes), illustrating how the combinatorial inclusion-exclusion principle may serve as an alternative to more advanced methods of studying their face numbers.

Combinatorics · Mathematics 2015-03-13 Michal Adamaszek

We design an FPRAS to count the number of bases of any matroid given by an independent set oracle, and to estimate the partition function of the random cluster model of any matroid in the regime where $0<q<1$. Consequently, we can sample…

Data Structures and Algorithms · Computer Science 2019-01-23 Nima Anari , Kuikui Liu , Shayan Oveis Gharan , Cynthia Vinzant