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Related papers: On ideal minimally non-packing clutters

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We extend the definition of chordal from graphs to clutters. The resulting family generalizes both chordal graphs and matroids, and obeys many of the same algebraic and geometric properties. Specifically, the independence complex of a…

Combinatorics · Mathematics 2021-08-24 Russ Woodroofe

Let K be a finite field and let X be a subset of a projective space, over the field K, which is parameterized by monomials arising from the edges of a clutter. We show some estimates for the degree-complexity, with respect to the revlex…

Commutative Algebra · Mathematics 2012-08-03 Eliseo Sarmiento , Maria Vaz Pinto , Rafael H. Villarreal

Let C be a clutter and let A be its incidence matrix. If the linear system x>=0;xA<=1 has the integer rounding property, we give a description of the canonical module and the a-invariant of certain normal subrings associated to C. If the…

Commutative Algebra · Mathematics 2011-04-05 Luis A. Dupont , Carlos Renteria-Marquez , Rafael H. Villarreal

A {\it clutter} (or {\it antichain} or {\it Sperner family}) $L$ is a pair $(V,E)$, where $V$ is a finite set and $E$ is a family of subsets of $V$ none of which is a subset of another. Normally, the elements of $V$ are called {\it…

Discrete Mathematics · Computer Science 2018-07-18 Vahan Mkrtchyan , Hovhannes Sargsyan

We introduce the concept of edgewise domination in clutters, and use it to provide an upper bound for the projective dimension of any squarefree monomial ideal. We then use a simple recursion to recover a formula for the projective…

Commutative Algebra · Mathematics 2013-05-09 Hailong Dao , Jay Schweig

A challenge of molecular self-assembly is to understand how to design particles that self-assemble into a desired structure and not any of a potentially large number of undesired structures. Here we use simulation to show that a strategy of…

Statistical Mechanics · Physics 2017-02-27 Stephen Whitelam

In this paper we give a classification of complete intersection vanishing ideals on parameterized sets of clutter type over finite fields.

Commutative Algebra · Mathematics 2018-01-10 Azucena Tochimani , Rafael H. Villarreal

We use computational experiments to find the rectangles of minimum perimeter into which a given number n of non-overlapping congruent circles can be packed. No assumption is made on the shape of the rectangles. In many of the packings…

Metric Geometry · Mathematics 2009-04-03 Boris D. Lubachevsky , Ronald L. Graham

This paper concerns the study of a class of clutters called simplicial subclutters. Given a clutter $\mathcal{C}$ and its simplicial subclutter $\mathcal{D}$, we compare some algebraic properties and invariants of the ideals $I, J$…

Commutative Algebra · Mathematics 2020-10-05 Mina Bigdeli , Ali Akbar Yazdan Pour

A tame ideal is an ideal $I$ such that the blowup of the affine space $\mathbb{A}_k^n$ along $I$ is regular. In this paper, we give a combinatorial characterization of tame squarefree monomial ideals. More precisely, we show that a square…

Commutative Algebra · Mathematics 2016-02-09 Abbas Nasrollah Nejad , Ashkan Nikseresht , Ali Akbar Yazdan Pour , Rashid Zaare-Nahandi

We examine an important combinatorial challenge in clearing clutter using a mobile robot equipped with a manipulator, seeking to compute an optimal object removal sequence for minimizing the task completion time, assuming that each object…

Robotics · Computer Science 2019-06-03 Wei N. Tang , Jingjin Yu

Let C be a clutter and let I be its edge ideal. We present a combinatorial description of the minimal generators of the symbolic Rees algebra Rs(I) of I. It is shown that the minimal generators of Rs(I) are in one to one correspondence with…

Commutative Algebra · Mathematics 2011-10-24 Jose Martinez-Bernal , Carlos Renteria , Rafael H. Villarreal

In this paper, we provide a complete description of the minimal primes of ideals generated by adjacent $2$-minors, in terms of the so-called admissible sets and associated lattice ideals. We prove that for these ideals, the properties of…

Commutative Algebra · Mathematics 2025-12-29 Takayuki Hibi , Francesco Navarra , Ayesha Asloob Qureshi , Sara Saeedi Madani

In this paper, we provide a combinatorial characterization of those collections of cells whose inner $2$-minor ideals are complete intersections. More precisely, given a collection of cells $\mathcal C$ and its associated inner $2$-minor…

Commutative Algebra · Mathematics 2026-03-24 Rodica Dinu , Francesco Navarra

A graph $G$ is said to be chordal if it has no induced cycles of length four or more. In a recent preprint Culbertson, Guralnik, and Stiller give a new characterization of chordal graphs in terms of sequences of what they call…

Combinatorics · Mathematics 2021-02-25 Anton Dochtermann

Motivated by classical work of Alon and F\"uredi, we introduce and address the following problem: determine the minimum number of affine hyperplanes in $\mathbb{R}^d$ needed to cover every point of the triangular grid $T_d(n) :=…

Combinatorics · Mathematics 2023-07-26 Abdul Basit , Alexander Clifton , Paul Horn

Let $D$ be a non-pseudoconvex open set in $\C^3$ and $S$ be the union of all two-dimensional planes with non-empty and non-pseudoconvex intersection with $D.$ Sufficient conditions are given for $\C^3\setminus S$ to belong to a complex…

Complex Variables · Mathematics 2012-11-19 Nikolai Nikolov , Peter Pflug

Let $I$ be the edge ideal of a clutter $\mathcal{C}$ in a polynomial ring $S$. In this paper, we present estimations of the Stanley depth of $I$ as well as the Stanley regularity of $S/I$, in terms of combinatorial data from the clutter…

Commutative Algebra · Mathematics 2014-01-07 Yi-Huang Shen

Motivated by using combinatorics to study jets of monomial ideals, we extend a definition of jets from graphs to clutters. We offer some structural results on their vertex covers, and show an interesting connection between the cover ideal…

Commutative Algebra · Mathematics 2024-07-03 Federico Galetto , Nicholas Iammarino , Teresa Yu

This letter deals with the problem of clutter edge detection and localization in training data. To this end, the problem is formulated as a binary hypothesis test assuming that the ranks of the clutter covariance matrix are known, and…

Signal Processing · Electrical Eng. & Systems 2022-03-14 Tianqi Wang , Da Xu , Chengpeng Hao , Pia Addabbo , Danilo Orlando