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Related papers: M-vector analogue for the cd-index

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This thesis aims to give the reader an introduction and overview of the cd-index of a poset, as well as establish some new results. We give a combinatorial proof of Ehrenborg and Karu's cd-index subdivision decomposition for Gorenstein*…

Combinatorics · Mathematics 2016-10-04 Patrick Dornian

We obtain computational hardness results for f-vectors of polytopes by exhibiting reductions of the problems DIVISOR and SEMI-PRIME TESTABILITY to problems on f-vectors of polytopes. Further, we show that the corresponding problems for…

Combinatorics · Mathematics 2021-09-20 Eran Nevo

Results of R. Stanley and M. Masuda completely characterize the h-vectors of simplicial posets whose order complexes are spheres. In this paper we examine the corresponding question in the case where the order complex is a ball. Using the…

Combinatorics · Mathematics 2010-09-13 Samuel Kolins

The convex hull of the set of the incidence vectors of the matchings of a graph G is the matching polytope of the graph, M(G). The graph whose vertices and edges are the vertices and edges of M(G) is the skeleton of the matching polytope of…

Combinatorics · Mathematics 2017-04-04 Nair Abreu , Liliana Costa , Carlos Henrique do Nascimento , Laura Patuzzi

Polytope theory has produced a great number of remarkably simple and complete characterization results for face-number sets or f-vector sets of classes of polytopes. We observe that in most cases these sets can be described as the…

Metric Geometry · Mathematics 2020-01-28 Hannah Sjöberg , Günter M. Ziegler

In this paper, we introduce the enough $g$-pairs property for a principal coefficients cluster algebra, which can be understood as a strong version of the sign-coherence of the $G$-matrices. Then we prove that any skew-symmetrizable…

Representation Theory · Mathematics 2020-07-24 Peigen Cao , Fang Li

We compute the $cd$-index $\Psi_{cd}$ of matroid base polytopes $\mathscr{P}(M)$ for a large family of matroids $M$. The $cd$-index is a polynomial in two non-commutative variables that compactly encodes the count of face flags $\mathcal{F}…

Combinatorics · Mathematics 2025-12-08 Tommaso Faustini , Alejandro Vargas

This note defines a complete h-vector for convex polytopes, which extends the already known toric (or mpih) h-vector and has many similar properties. Complete means that it encodes the whole of the flag vector. First we define the concept…

Combinatorics · Mathematics 2009-12-01 Jonathan Fine

We prove tight lower bounds for the coefficients of the generalized $h$-vector of a rational polytope with a symmetry of prime order that is fixed--point--free on the boundary. These bounds generalize results of R.~Stanley and R.~Adin for…

Algebraic Geometry · Mathematics 2007-05-23 A. A'Campo-Neuen

In this article we define an algebraic vertex of a generalized polyhedron and show that it is the smallest set of points needed to define the polyhedron. We prove that the indicator function of a generalized polytope $P$ is a linear…

Metric Geometry · Mathematics 2017-01-06 Arseniy Akopyan , Imre Bárány , Sinai Robins

This thesis focuses on algebraic shifting and its applications to f-vector theory of simplicial complexes and more general graded posets. In particular, several approaches and partial results concerning the g-conjecture for simplicial…

Combinatorics · Mathematics 2007-09-21 Eran Nevo

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

The M-polynomial provides a unifying framework for a wide class of degree-based topological indices. Despite its structural importance, general methods for computing the M-polynomial under graph constructions remain limited. In this paper,…

Combinatorics · Mathematics 2026-03-12 El-Mehdi Mehiri , Sandi Klavžar

A Gelfand-Cetlin polytope is a convex polytope obtained as an image of certain completely integrable system on a partial flag variety. In this paper, we give an equivalent description of the face structure of a GC-polytope in terms of so…

Combinatorics · Mathematics 2021-01-11 Byung Hee An , Yunhyung Cho , Jang Soo Kim

For a $d$-dimensional polytope with $v$ vertices, $d+1\le v\le2d$, we calculate precisely the minimum possible number of $m$-dimensional faces, when $m=1$ or $m\ge0.62d$. This confirms a conjecture of Gr\"unbaum, for these values of $m$.…

Combinatorics · Mathematics 2019-01-17 Guillermo Pineda-Villavicencio , Julien Ugon , David Yost

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

In a previous article, we proved tight lower bounds for the coefficients of the generalized $h$-vector of a centrally symmetric rational polytope using intersection cohomology of the associated projective toric variety. Here we present a…

Algebraic Geometry · Mathematics 2007-05-23 Annette A'Campo-Neuen

We classify projective toric manifolds whose dual variety is not a hypersurface in the dual projective space. Under the standard dictionary between toric geometry and convex geometry, they correspond to certain convex Delzant integer…

Algebraic Geometry · Mathematics 2007-05-23 Sandra Di Rocco

We prove a simple formula for arbitrary cluster variables in the marked surfaces model. As part of the formula, we associate a labeled poset to each tagged arc, such that the associated $F$-polynomial is a weighted sum of order ideals. Each…

Combinatorics · Mathematics 2024-04-19 Vincent Pilaud , Nathan Reading , Sibylle Schroll

We prove that if a standard determinantal scheme is level, then its h-vector is a log-concave pure O-sequence, and conjecture that the converse also holds. Among other cases, we prove the conjecture in codimension two, or when the entries…

Commutative Algebra · Mathematics 2014-03-06 Alexandru Constantinescu , Matey Mateev