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Related papers: An entropy argument for counting matroids

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We use entropy numbers in combination with the polynomial method to derive a new general lower bound for the n-th minimal error in the quantum setting of information-based complexity. As an application, we improve some lower bounds on…

Quantum Physics · Physics 2007-05-23 Stefan Heinrich

Consider a matroid where all elements are labeled with an element in $\mathbb{Z}$. We are interested in finding a base where the sum of the labels is congruent to $g \pmod m$. We show that this problem can be solved in $\tilde{O}(2^{4m} n…

Combinatorics · Mathematics 2024-03-22 Siyue Liu , Chao Xu

We prove an extension of Yuan's Lemma to more than two matrices, as long as the set of matrices has rank at most 2. This is used to generalize the main result of [A. Baccari and A. Trad. On the classical necessary second-order optimality…

Optimization and Control · Mathematics 2017-07-20 Gabriel Haeser

Given an $n$-connected binary matroid, we obtain a necessary and sufficient condition for its single-element coextensions to be $n$-connected.

Combinatorics · Mathematics 2018-12-05 Ganesh Mundhe , Y. M. Borse

We generalize the well-studied notion of a modular pair of a finite matroid to arbitrary families of sets in infinite matroids, and use it to develop the theory of infinite matroids in several as-yet-unexplored areas. Our results include a…

Combinatorics · Mathematics 2026-04-23 Mattias Ehatamm , Peter Nelson , Fernanda Rivera Omana

We study a matrix-based notion of matroid representation over local commutative rings obtained by replacing linear independence with modular independence. This construction always defines an independence system, though not necessarily a…

Combinatorics · Mathematics 2026-03-11 Koji Imamura , Keisuke Shiromoto

Let $M$ be a matroid defined on a finite set $E$ and $L\subset E$. $L$ is locked in $M$ if $M|L$ and $M^*|(E\backslash L)$ are 2-connected, and $min\{r(L), r^*(E\backslash L)\} \geq 2$. Locked subsets characterize nontrivial facets of the…

Computational Complexity · Computer Science 2019-06-20 Brahim Chaourar

We obtain the entropy of flexible linear chains composed of M monomers placed on the square lattice using a transfer matrix approach. An excluded volume interaction is included by considering the chains to be self-and mutually avoiding, and…

Statistical Mechanics · Physics 2009-11-07 W. G. Dantas , J. F. Stilck

We present a strengthening of the countable Menger theorem (edge version) of R. Aharoni. Let $ D=(V,A) $ be a countable digraph with $ s\neq t\in V $ and let $\mathcal{M}=\bigoplus_{v\in V}\mathcal{M}_v $ be a matroid on $ A $ where $…

Combinatorics · Mathematics 2017-05-02 Attila Joó

Recently there has been several works estimating the number of $n\times n$ matrices with elements from some finite sets $\mathcal X$ of arithmetic interest and of a given determinant. Typically such results are compared with the trivial…

Number Theory · Mathematics 2024-08-09 Ilya D. Shkredov , Igor E. Shparlinski

Let $G$ be a finite connected graph, and let $T$ be a spanning tree of $G$ chosen uniformly at random. The work of Kirchhoff on electrical networks can be used to show that the events $e_1 \in T$ and $e_2 \in T$ are negatively correlated…

Combinatorics · Mathematics 2022-08-05 June Huh , Benjamin Schröter , Botong Wang

For all positive integers $\ell$ and $r$, we determine the maximum number of elements of a simple rank-$r$ positroid without the rank-$2$ uniform matroid $U_{2,\ell+2}$ as a minor, and characterize the matroids with the maximum number of…

Combinatorics · Mathematics 2025-12-18 Jonathan Boretsky , Zach Walsh

We study the algebraic matroid induced by the ideal of (r+1)-minors of a matrix of variables over a field. This is inherently connected to the bounded-rank matrix completion problem, in which the aim is to complete a partially observed rank…

Commutative Algebra · Mathematics 2026-01-09 Lisa Nicklasson , Manolis C. Tsakiris

This paper initiates the study of quantum algorithms for matroid property problems. It is shown that quadratic quantum speedup is possible for the calculation problem of finding the girth or the number of circuits (bases, flats,…

Quantum Physics · Physics 2022-03-28 Xiaowei Huang , Jingquan Luo , Lvzhou Li

A clutter consists of a finite set and a collection of pairwise incomparable subsets. Clutters are natural generalisations of matroids, and they have similar operations of deletion and contraction. We introduce a notion of connectivity for…

Combinatorics · Mathematics 2017-03-06 Amanda Cameron , Dillon Mayhew

We study the problem of fair allocation of a set of indivisible items among agents with additive valuations, under matroid constraints and two generalizations: $p$-extendible system and independence system constraints. The objective is to…

Computer Science and Game Theory · Computer Science 2024-11-07 Yuanyuan Wang , Xin Chen , Qingqin Nong

We study density thresholds that force a measurable set $E\subseteq\mathbb{R}^d$ to contain all sufficiently large similar copies of every $n$-point configuration. We prove a lower bound of the form $1-O((\log n)/n)$, which matches the…

Classical Analysis and ODEs · Mathematics 2026-04-21 Vjekoslav Kovač , Adian Anibal Santos Sepčić

Let $P(n)$ be the number of polyominoes of $n$ cells and $\lambda$ be Klarner's constant, that is, $\lambda=\lim_{n\to\infty} \sqrt[n]{P(n)}$. We show that there exist some positive numbers $A,T$, so that for every $n$ \[ P(n) \ge…

Combinatorics · Mathematics 2025-07-15 Vuong Bui

We show that, if $\alpha > 0$ is a real number, $n \ge 2$ and $\ell \ge 2$ are integers, and $q$ is a prime power, then every simple matroid $M$ of sufficiently large rank, with no $U_{2,\ell}$-minor, no rank-$n$ projective geometry minor…

Combinatorics · Mathematics 2012-10-17 Jim Geelen , Peter Nelson

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