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Related papers: An entropy argument for counting matroids

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We show that the entropy of a hyperbolic group acting on its ideal boundary is closely related to the exponential rate of its growth.

Differential Geometry · Mathematics 2007-05-23 A. Bis , P. G. Walczak

We introduce a new iterative rounding technique to round a point in a matroid polytope subject to further matroid constraints. This technique returns an independent set in one matroid with limited violations of the other ones. On top of the…

Data Structures and Algorithms · Computer Science 2018-11-26 André Linhares , Neil Olver , Chaitanya Swamy , Rico Zenklusen

We establish a relative Bertini type theorem for multiplier ideal sheaves. Then we prove a relative version of the Koll\'ar--Nadel type vanishing theorem as an application.

Algebraic Geometry · Mathematics 2018-02-20 Osamu Fujino

We discuss a conjecture of Ingleton on excluded minors for base-orderability, and, extending a result he stated, we prove that infinitely many of the matroids that he identified are excluded minors for base-orderability, as well as for the…

Combinatorics · Mathematics 2024-08-07 Joseph E. Bonin , Thomas J. Savitsky

Behavior of the entropy numbers of classes of multivariate functions with mixed smoothness is studied here. This problem has a long history and some fundamental problems in the area are still open. The main goal of this paper is to develop…

Numerical Analysis · Mathematics 2016-03-01 V. Temlyakov

We present a sharp upper bound for the number of generators of a finite group in terms of the ratio between the order and the exponent.

Group Theory · Mathematics 2025-08-28 Luca Sabatini

Let $\cM$ be a minor-closed class of matroids that does not contain arbitrarily long lines. The growth rate function, $h:\bN\rightarrow \bN$ of $\cM$ is given by $$h(n) = \max(|M|\, : \, M\in \cM, simple, rank-$n$).$$ The Growth Rate…

Combinatorics · Mathematics 2011-11-01 Jim Geelen , Peter Nelson

Matroid interdiction problems are well-researched in the field of combinatorial optimization. In the matroid $\ell$-interdiction problem, an interdiction strategy removes a subset of cardinality $\ell$ from the matroid's ground set. The…

Combinatorics · Mathematics 2025-11-17 Nils Hausbrandt , Levin Nemesch , Stefan Ruzika

For any integers $d, n \geq 2$ and $1/({\min\{n,d\}})^{0.4999} < \varepsilon<1$, we show the existence of a set of $n$ vectors $X\subset \mathbb{R}^d$ such that any embedding $f:X\rightarrow \mathbb{R}^m$ satisfying $$ \forall x,y\in X,\…

Information Theory · Computer Science 2017-11-10 Kasper Green Larsen , Jelani Nelson

Although many authors have considered how many ternary comparisons it takes to sort a multiset $S$ of size $n$, the best known upper and lower bounds still differ by a term linear in $n$. In this paper we restrict our attention to online…

Data Structures and Algorithms · Computer Science 2009-07-07 Travis Gagie , Yakov Nekrich

In the Inverse Matroid problem, we are given a matroid, a fixed basis $B$, and an initial weight function, and the goal is to minimally modify the weights -- measured by some function -- so that $B$ becomes a maximum-weight basis. The…

Data Structures and Algorithms · Computer Science 2025-07-03 Kristóf Bérczi , Lydia Mirabel Mendoza-Cadena , José Soto

Let $ X_1, \ldots, X_n $ be independent random variables taking values in the alphabet $ \{0, 1, \ldots, r\} $, and $ S_n = \sum_{i = 1}^n X_i $. The Shepp--Olkin theorem states that, in the binary case ($ r = 1 $), the Shannon entropy of $…

Information Theory · Computer Science 2022-05-10 Mladen Kovačević

In this paper, we introduce the Maximum Matrix Contraction problem, where we aim to contract as much as possible a binary matrix in order to maximize its density. We study the complexity and the polynomial approximability of the problem.…

Computational Complexity · Computer Science 2023-06-05 Dimitri Watel , Pierre-Louis Poirion

Consider a real matrix $\Theta$ consisting of rows $(\theta_{i,1},\ldots,\theta_{i,n})$, for $1\leq i\leq m$. The problem of making the system linear forms $x_{1}\theta_{i,1}+\cdots+x_{n}\theta_{i,n}-y_{i}$ for integers $x_{j},y_{i}$ small…

Number Theory · Mathematics 2022-09-07 Johannes Schleischitz

We discuss linear programming techniques that help to deduce corollaries of non classic inequalities for Shannon's entropy. We focus on direct applications of the copy lemma. These applications involve implicitly some (known or unknown)…

Information Theory · Computer Science 2019-07-04 Emirhan Gürpınar , Andrei Romashchenko

Graphings serve as limit objects for bounded-degree graphs. We define the ``cycle matroid'' of a graphing as a submodular setfunction, with values in [0,1], which generalizes (up to normalization) the cycle matroid of finite graphs. We…

Combinatorics · Mathematics 2023-11-08 László Lovász

Topologically constrained genome-like polymers often double-fold into tree-like configurations. Here we calculate the exact number of tightly double-folded configurations available to a ring polymer in ideal conditions. For this purpose, we…

Soft Condensed Matter · Physics 2026-03-02 Pieter H. W. van der Hoek , Angelo Rosa , Elham Ghobadpour , Ralf Everaers

Seymour's decomposition theorem is a hallmark result in matroid theory presenting a structural characterization of the class of regular matroids. Formalization of matroid theory faces many challenges, most importantly that only a limited…

We improve the upper bound for the maximum possible number of stable matchings among $n$ jobs and $n$ applicants from $131072^n+O(1)$ to $3.55^n+O(1)$. To establish this bound, we state a novel formulation of a certain entropy bound that is…

Combinatorics · Mathematics 2021-06-07 Cory Palmer , Dömötör Pálvölgyi

Thin sums matroids were introduced to extend the notion of representability to non-finitary matroids. We give a new criterion for testing when the thin sums construction gives a matroid. We show that thin sums matroids over thin families…

Combinatorics · Mathematics 2012-04-30 Hadi Afzali , Nathan Bowler