English
Related papers

Related papers: Powers of Edge Ideals with Linear Resolutions

200 papers

We study the asymptotic behavior of the ideals of minors in minimal free resolutions over local rings. In particular, we prove that such ideals are eventually 2-periodic over complete intersections and Golod rings. We also establish general…

Commutative Algebra · Mathematics 2025-06-16 Michael K. Brown , Hailong Dao , Prashanth Sridhar

For a graph G, its rth power G^r has the same vertex set as G, and has an edge between any two vertices within distance r of each other in G. We give a lower bound for the number of edges in the rth power of G in terms of the order of G and…

Combinatorics · Mathematics 2012-02-29 Alexey Pokrovskiy

We study a family of monomial ideals, called block diagonal matching field ideals, which arise as monomial Gr\"obner degenerations of determinantal ideals. Our focus is on the minimal free resolutions of these ideals and all of their…

Commutative Algebra · Mathematics 2025-01-29 Oliver Clarke , Fatemeh Mohammadi

A connected graph $G$ with a perfect matching is said to be $k$-extendable for integers $k$, $1 \leq k\leq \frac{|V(G)|}{2}-1$, if any matching in $G$ of size $k$ is contained in a perfect matching of $G$. A $k$-extendable graph is minimal…

Combinatorics · Mathematics 2025-10-07 Jing Guo , Fuliang Lu , Heping Zhang

Let $I$ be a square-free monomial ideal $I$ of projective dimension one. Starting with the Taylor complex on the generators of $I^r$, we use Discrete Morse theory to describe a CW complex that supports a minimal free resolution of $I^r$. To…

Commutative Algebra · Mathematics 2021-11-03 Susan Cooper , Sabine El Khoury , Sara Faridi , Sarah Mayes-Tang , Susan Morey , Liana M. Sega , Sandra Spiroff

Given an edge ideal of graph G, we show that if the first nonlinear strand in the resolution of $I_G$ is zero until homological stage $a_1$, then the next nonlinear strand in the resolution is zero until homological stage $2a_1$.…

Commutative Algebra · Mathematics 2010-12-02 Gwyneth Whieldon

Let $I_1,\dots,I_n$ be ideals generated by linear forms in a polynomial ring over an infinite field and let $J = I_1 \cdots I_n$. We describe a minimal free resolution of $J$ and show that it is supported on a polymatroid obtained from the…

Commutative Algebra · Mathematics 2022-08-24 Aldo Conca , Manolis C. Tsakiris

We graph-theoretically characterize triangle-free Gorenstein graphs $G$. As an application, we classify when $I(G)^2$ is Cohen-Macaulay.

Commutative Algebra · Mathematics 2015-09-01 Do Trong Hoang , Tran Nam Trung

We study simple graphs for which the maximal homogeneous ideal is an associated prime of the second power of their closed neighborhood ideals. In particular, we show that such graphs must have diameter at most $6$, and that those with…

Commutative Algebra · Mathematics 2025-07-14 Ha Thi Thu Hien , Thanh Vu

In this paper, we introduce techniques for producing normal square-free monomial ideals from old such ideals. These techniques are then used to investigate the normality of cover ideals under some graph operations. Square-free monomial…

We show that the minimal resolution of the quotient of the polynomial algebra over a field by a cointerval edge ideal can be given the structure of a DG-algebra.

Commutative Algebra · Mathematics 2016-09-26 Emil Sköldberg

Let $G$ be a finite simple graph on $n$ non-isolated vertices, and let $J_G$ be its binomial edge ideal. We determine almost all pairs $(\text{projdim}(J_G),\text{reg}(J_G))$, where $G$ ranges over all finite simple graphs on $n$…

Commutative Algebra · Mathematics 2025-01-15 Antonino Ficarra , Emanuele Sgroi

A matching covered graph $G$ is minimal if for each edge $e$ of $G$, $G-e$ is not matching covered. An edge $e$ of a matching covered graph $G$ is removable if $G-e$ is also matching covered. Thus a matching covered graph is minimal if and…

Combinatorics · Mathematics 2024-05-28 Yipei Zhang , Xiumei Wang , Jinjiang Yuan , C. T. Ng , T. C. E. Cheng

We consider the edge ideals of large classes of graphs with whiskers and for these ideals we prove that the arithmetical rank is equal to the big height. Then we extend these results to other classes of squarefree monomial ideals, generated…

Commutative Algebra · Mathematics 2013-07-08 Antonio Macchia

Given a family $\mathcal{F}$ of graphs, a graph is \emph{$\mathcal{F}$-subgraph-free} if it has no subgraph isomorphic to a member of $\mathcal{F}$. We present a fixed-parameter linear-time algorithm that decides whether a planar graph can…

Discrete Mathematics · Computer Science 2025-10-20 Shinwoo An , Seonghyuk Im , Seokbeom Kim , Myounghwan Lee

A graph $G$ is $\textit{universal}$ for a (finite) family $\mathcal{H}$ of graphs if every $H \in \mathcal{H}$ is a subgraph of $G$. For a given family $\mathcal{H}$, the goal is to determine the smallest number of edges an…

Combinatorics · Mathematics 2024-01-12 Noga Alon , Natalie Dodson , Carmen Jackson , Rose McCarty , Rajko Nenadov , Lani Southern

For a monomial ideal $I$, let $G(I)$ be its minimal set of monomial generators. If there is a total order on $G(I)$ such that the corresponding Lyubeznik resolution of $I$ is a minimal free resolution of $I$, then $I$ is called a Lyubeznik…

Commutative Algebra · Mathematics 2013-12-03 Jin Guo , Tongsuo Wu , Houyi Yu

We prove that every $n$-vertex $K_t$-minor-free graph $G$ of maximum degree $\Delta$ has a set $F$ of $O(t^2(\log t)^{1/4}\sqrt{\Delta n})$ edges such that every component of $G - F$ has at most $n/2$ vertices. This is best possible up to…

Combinatorics · Mathematics 2023-10-24 Gwenaël Joret , William Lochet , Michał T. Seweryn

This paper is concerned with the question of whether geometric structures such as cell complexes can be used to simultaneously describe the minimal free resolutions of all powers of a monomial ideal. We provide a full answer in the case of…

Commutative Algebra · Mathematics 2021-08-18 Susan M. Cooper , Sabine El Khoury , Sara Faridi , Sarah Mayes-Tang , Susan Morey , Liana M. Sega , Sandra Spiroff

The diamond is the graph obtained by removing an edge from the complete graph on 4 vertices. A graph is ($P_6$, diamond)-free if it contains no induced subgraph isomorphic to a six-vertex path or a diamond. In this paper we show that the…

Combinatorics · Mathematics 2021-06-17 Jan Goedgebeur , Shenwei Huang , Yiao Ju , Owen Merkel