English
Related papers

Related papers: On licci squarefree monomial ideals

200 papers

We compute the Betti numbers for all the powers of initial and final lexsegment edge ideals. For the powers of the edge ideal of an anti-$d-$path, we prove that they have linear quotients and we characterize the normally torsion-free…

Commutative Algebra · Mathematics 2011-12-01 Carmela Ferro , Mariella Murgia , Oana Olteanu

We introduce the notion of sortability and $t$-sortability for a simplicial complex and study the graphs for which their independence complexes are either sortable or $t$-sortable. We show that the proper interval graphs are precisely the…

Commutative Algebra · Mathematics 2019-08-21 Jürgen Herzog , Fahimeh Khosh-Ahang , Somayeh Moradi , Masoomeh Rahimbeigi

Let $R=K[x_1,\ldots,x_n]$ be the polynomial ring in $n$ variables over a field $K$. We show that if $G$ is a connected graph with a basic $5$-cycle $C$, then $G$ is a sequentially Cohen-Macaulay graph if and only if there exists a shedding…

Commutative Algebra · Mathematics 2024-05-24 Mozhgan Koolani , Amir Mafi

We study the topology of the lcm-lattice of edge ideals and derive upper bounds on the Castelnuovo-Mumford regularity of the ideals. In this context it is natural to restrict to the family of graphs with no induced 4-cycle in their…

Combinatorics · Mathematics 2009-09-16 Eran Nevo

Let $G$ be a simple graph on $n$ vertices and let $J_{G,m}$ be the generalized binomial edge ideal associated to $G$ in the polynomial ring $K[x_{ij}, 1\le i \le m, 1\le j \le n]$. We classify the Cohen-Macaulay generalized binomial edge…

Commutative Algebra · Mathematics 2023-07-04 Luca Amata , Marilena Crupi , Giancarlo Rinaldo

When a monomial ideal has linear quotients with respect to an admissible order of increasing support-degree, we provide two proofs of different flavors to show that it is componentwise support-linear. We also introduce the variable…

Commutative Algebra · Mathematics 2014-04-09 Yi-Huang Shen

We study monomial ideals with linear presentation or partially linear resolution. We give combinatorial characterizations of linear presentation for square-free ideals of degree 3, and for primary ideals whose resolutions are linear except…

Commutative Algebra · Mathematics 2022-04-01 Hailong Dao , David Eisenbud

Let R be a commutative Noetherian ring. Licci ideals are the ideals of R that can be linked in a finite number of steps to a complete intersection. Each licci ideal admits a rigid deformation, and two licci ideals are in the same Herzog…

Commutative Algebra · Mathematics 2025-06-12 Lorenzo Guerrieri , Xianglong Ni , Jerzy Weyman

We define a new combinatorial object, which we call a labeled hypergraph, uniquely associated to any square-free monomial ideal. We prove several upper bounds on the regularity of a square-free monomial ideal in terms of simple…

Commutative Algebra · Mathematics 2013-04-02 Kuei-Nuan Lin , Jason McCullough

In this paper, our main focus is to explore different classes of nearly normally torsion-free ideals. We first characterize all finite simple connected graphs with nearly normally torsion-free cover ideals. Next, we characterize all…

Commutative Algebra · Mathematics 2022-06-02 Mehrdad Nasernejad , Ayesha Asloob Qureshi , Kazem Khashyarmanesh , Leslie G. Roberts

The path ideal (of length t >=2) of a graph G is the monomial ideal, denoted I_t(G), whose generators correspond to the directed paths of length t in G. We study some of the algebraic properties of I_t(G) when G is a tree. We first show…

Commutative Algebra · Mathematics 2009-10-06 Jing Jane He , Adam Van Tuyl

Let $S=K[x_1,\ldots,x_n]$ be the polynomial ring in $n$ variables over a field $K$ and $I\subset S$ a squarefree monomial ideal. In the present paper we are interested in the monomials $u \in S$ belonging to the socle $\Soc(S/I^{k})$ of…

Commutative Algebra · Mathematics 2013-08-27 Jürgen Herzog , Takayuki Hibi

Let $G$ be a simple graph on $n$ vertices. Let $L_G \text{ and } \mathcal{I}_G \: $ denote the Lov\'asz-Saks-Schrijver(LSS) ideal and parity binomial edge ideal of $G$ in the polynomial ring $S = \mathbb{K}[x_1,\ldots, x_n, y_1, \ldots,…

Commutative Algebra · Mathematics 2021-12-07 Arvind Kumar

We find a class of block graphs whose binomial edge ideals have minimal regularity. As a consequence, we characterize the trees whose binomial edge ideals have minimal regularity. Also, we show that the binomial edge ideal of a block graph…

Commutative Algebra · Mathematics 2014-02-11 Faryal Chaudhry , Ahmet Dokuyucu , Rida Irfan

A cut ideal of a graph records the relations among the cuts of the graph. These toric ideals have been introduced by Sturmfels and Sullivant who also posed the problem of relating their properties to the combinatorial structure of the…

Commutative Algebra · Mathematics 2009-04-28 Uwe Nagel , Sonja Petrović

We introduce binomial edge ideals attached to a simple graph $G$ and study their algebraic properties. We characterize those graphs for which the quadratic generators form a Gr\"obner basis in a lexicographic order induced by a vertex…

Commutative Algebra · Mathematics 2009-10-16 Juergen Herzog , Takayuki Hibi , Freyja Hreinsdottir , Thomas Kahle , Johannes Rauh

In this paper we provide a full combinatorial characterization of sequentially Cohen-Macaulay binomial edge ideals of closed graphs. In addition, we show that a binomial edge ideal of a closed graph is approximately Cohen-Macaulay if and…

Commutative Algebra · Mathematics 2022-07-12 Viviana Ene , Giancarlo Rinaldo , Naoki Terai

As a higher analogue of the edge ideal of a graph, we study the $t$-connected ideal $\operatorname{J}_{t}$. This is the monomial ideal generated by the connected subsets of size $t$. For chordal graphs, we show that $\operatorname{J}_{t}$…

Commutative Algebra · Mathematics 2025-04-02 H. Ananthnarayan , Omkar Javadekar , Aryaman Maithani

We characterize all graphs whose binomial edge ideals have pure resolutions. Moreover, we introduce a new switching of graphs which does not change some algebraic invariants of graphs, and using this, we study the linear strand of the…

Combinatorics · Mathematics 2014-01-22 Dariush Kiani , Sara Saeedi Madani

We apply some basic notions from combinatorial topology to establish various algebraic properties of edge ideals of graphs and more general Stanley-Reisner rings. In this way we provide new short proofs of some theorems from the literature…

Combinatorics · Mathematics 2008-10-23 Anton Dochtermann , Alexander Engstrom