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Using factorization theorems for sparse polynomials, we compute the trace field of Dehn fillings of the Whitehead link, and (assuming Lehmer's Conjecture) the minimal polynomial of the small dilatation pseudo-Anosov maps and the trace field…

Geometric Topology · Mathematics 2022-09-20 Michael Filaseta , Stavros Garoufalidis

We study combinatorial inequalities for various classes of set systems: matroids, polymatroids, poset antimatroids, and interval greedoids. We prove log-concavity inequalities for counting certain weighted feasible words, which generalize…

Combinatorics · Mathematics 2024-08-01 Swee Hong Chan , Igor Pak

For each permutation $w$, we consider the set $\mathrm{PD}(w)$ of reduced pipe dreams for $w$, partially ordered so that cover relations correspond to (generalized) chute moves. Settling a conjecture of Rubey from 2012, we prove that…

Combinatorics · Mathematics 2025-07-18 Ilani Axelrod-Freed , Colin Defant , Hanna Mularczyk , Son Nguyen , Katherine Tung

The Rayleigh property is a negative correlation property of electrical networks, which was generalized to matroids by Choe and Wagner. We prove that positroids, a class of matroid introduced by Postnikov which have seen many recent…

Combinatorics · Mathematics 2016-11-14 Cameron Marcott

Permutation Matrices are a well known class of matrices which encode the elements of the symmetric group on $d$ elements as a square $d\times d$ matrix. Motivated by [4], we define a similar class of matrices which are a generalization of…

Rings and Algebras · Mathematics 2024-03-06 Steven Robert Lippold

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

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

We report on various results, conjectures, and open problems related to Kazhdan-Lusztig polynomials of matroids. We focus on conjectures about the roots of these polynomials, all of which appear here for the first time.

Combinatorics · Mathematics 2017-03-16 Katie Gedeon , Nicholas Proudfoot , Benjamin Young

Restricted Whitney numbers of the first kind appear in the combinatorial recursion for the matroid Kazhdan-Lusztig polynomials. In the special case of braid matroids (the matroid associated to the partition lattice, the complete graph, the…

Combinatorics · Mathematics 2018-02-06 Trevor K. Karn , Max D. Wakefield

In this paper, we present Poisson brackets of certain classes of mappings obtained as general periodic reductions of integrable lattice equations. The Poisson brackets are derived using the so called Ostrogradsky transformation.

Exactly Solvable and Integrable Systems · Physics 2017-02-01 Dinh T. Tran , Peter H. van der Kamp , G. Reinout W. Quispel

We derive a series of results on random walks on a d-dimensional hypercubic lattice (lattice paths). We introduce the notions of terse and simple paths corresponding to the path having no backtracking parts (spikes). These paths label…

High Energy Physics - Lattice · Physics 2008-11-26 A. Gonzalez-Arroyo

A gaussoid is a combinatorial structure that encodes independence in probability and statistics, just like matroids encode independence in linear algebra. The gaussoid axioms of Lnenicka and Mat\'us are equivalent to compatibility with…

Combinatorics · Mathematics 2020-06-17 Tobias Boege , Alessio D'Alì , Thomas Kahle , Bernd Sturmfels

In this work, we study the well-posedness of certain sparse regularized linear regression problems, i.e., the existence, uniqueness and continuity of the solution map with respect to the data. We focus on regularization functions that are…

Statistics Theory · Mathematics 2024-09-06 Jasper Marijn Everink , Yiqiu Dong , Martin Skovgaard Andersen

We study the way in which equivariant Kazhdan-Lusztig polynomials, equivariant inverse Kazhdan-Lusztig polynomials, and equivariant Z-polynomials of matroids change under the operation of relaxation of a collection of stressed hyperplanes.…

Combinatorics · Mathematics 2022-02-15 Trevor Karn , George Nasr , Nicholas Proudfoot , Lorenzo Vecchi

The spectral moments of ensembles of sparse random block matrices are analytically evaluated in the limit of large order. The structure of the sparse matrix corresponds to the Erd\"os-Renyi random graph. The blocks are i.i.d. random…

Mathematical Physics · Physics 2022-04-13 Giovanni M. Cicuta , Mario Pernici

Leclerc and Zelevinsky described quasicommuting families of quantum minors in terms of a certain combinatorial condition, called weak separation. They conjectured that all maximal by inclusion weakly separated collections of minors have the…

Combinatorics · Mathematics 2015-06-12 Suho Oh , Alex Postnikov , David E Speyer

The stratification of the Grassmannian by positroid varieties has been the subject of extensive research. Positroid varieties are in bijection with a number of combinatorial objects, including $k$-Bruhat intervals and bounded affine…

Combinatorics · Mathematics 2016-10-18 Rachel Karpman

We generalise a sparsity condition for hypergraphs and show a result relating sparseness of hypergraphs to the decomposition of a modified incidence graph into edge-disjoint forests. We also give new sparsity conditions for posets and…

Combinatorics · Mathematics 2026-03-18 Signe Lundqvist , Tovohery Randrianarisoa , Klara Stokes , Joannes Vermant

We consider posets of lattice paths (endowed with a natural order) and begin the study of such structures. We give an algebraic condition to recognize which ones of these posets are lattices. Next we study the class of Dyck lattices (i.e.,…

Combinatorics · Mathematics 2007-05-23 Luca Ferrari , Renzo Pinzani

We determine the rank of a random matrix over an arbitrary field with prescribed numbers of non-zero entries in each row and column. As an application we obtain a formula for the rate of low-density parity check codes. This formula…

Combinatorics · Mathematics 2024-06-21 Amin Coja-Oghlan , Alperen A. Ergür , Pu Gao , Samuel Hetterich , Maurice Rolvien