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We survey recent studies on the Castelnuovo-Mumford regularity of edge ideals of graphs and their powers. Our focus is on bounds and exact values of $\text{reg} I(G)$ and the asymptotic linear function $\text{reg} I(G)^q$, for $q \geq 1,$…

Commutative Algebra · Mathematics 2022-09-28 Arindam Banerjee , Selvi Kara , Huy Tai Ha

Let $D$ be a weighted oriented graph with the underlying graph $G$ and $I(D), I(G) $ be the edge ideals corresponding to $D$ and $G$ respectively. We show that the regularity of edge ideal of a certain class of weighted oriented graph…

Combinatorics · Mathematics 2022-04-12 Mousumi Mandal , Dipak Kumar Pradhan

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 work, some combinatorial lower bound for regularity of powers of the edge ideal of a uniform hypergarph is gained. A family of hypergraphs whose regularity of edge ideal attains this bound and has a significant difference from the…

Commutative Algebra · Mathematics 2025-06-03 Fahimeh Khosh-Ahang Ghasr

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

An ideal $I$ of a commutative ring $R$ is said to be of linear type when its Rees algebra and symmetric algebra exhibit isomorphism. In this paper, we investigate the conjecture put forth by Jayanthan, Kumar, and Sarkar (2021) that if $G$…

Commutative Algebra · Mathematics 2025-05-06 Marie Amalore Nambi , Neeraj Kumar

If C is a clutter with n vertices and q edges whose clutter matrix has column vectors V={v1,...,vq}, we call C an Ehrhart clutter if {(v1,1),...,(vq,1)} is a Hilbert basis. Letting A(P) be the Ehrhart ring of P=conv(V), we are able to show…

Commutative Algebra · Mathematics 2011-04-05 Jose Martinez-Bernal , Edwin O'Shea , Rafael H. Villarreal

We construct the first linear strand of the minimal free resolutions of edge ideals of $d$-partite $d$-uniform clutters. We show that the first linear strand is supported on a relative simplicial complex. In the case that the edge ideals of…

Commutative Algebra · Mathematics 2020-12-07 Amin Nematbakhsh

Let G be a graph and let I be its edge ideal. Our main result shows that the sets of associated primes of the powers of I form an ascending chain. It is known that the sets of associated primes of I(i) and intcl(I(i)) stabilize for large i,…

Commutative Algebra · Mathematics 2012-08-21 Jose Martinez-Bernal , Susan Morey , Rafael H. Villarreal

We study the regularity of binomial edge ideals. For a closed graph $G$ we show that the regularity of the binomial edge ideal $J_G$ coincides with the regularity of $\ini_{\lex}(J_G)$ and can be expressed in terms of the combinatorial data…

Commutative Algebra · Mathematics 2013-07-09 Viviana Ene , Andrei Zarojanu

In this paper we provide some exact formulas for the regularity of powers of edge ideals of vertex-weighted oriented cycles and vertex-weighted unicyclic graphs. These formulas are functions of the weight of vertices and the number of…

Commutative Algebra · Mathematics 2019-04-05 Guangjun Zhu , Hong Wang , Li Xu , Jiaqi Zhang

Let $S=K[x_1, \ldots,x_n]$ denote the polynomial ring in $n$ variables over a field $K$ and let $I \subset S$ be a monomial ideal. For a vector $\mathfrak{c}\in\mathbb{N}^n$, we set $I_{\mathfrak{c}}$ to be the ideal generated by monomials…

Commutative Algebra · Mathematics 2025-02-05 Takayuki Hibi , Seyed Amin Seyed Fakhari

For the edge ideal $I(\D)$ of a weighted oriented graph $\D$, we prove that its symbolic powers $I(\D)^{(t)}$ are Cohen-Macaulay for all $t\geqslant 1$ if and only if the underlying graph $G$ is composed of a disjoint union of some complete…

Commutative Algebra · Mathematics 2025-09-11 Truong Thi Hien , Jiaxin Li , Tran Nam Trung , Guangjun Zhu

Take a prime power $q$, an integer $n\geq 2$, and a coordinate subspace $S\subseteq GF(q)^n$ over the Galois field $GF(q)$. One can associate with $S$ an $n$-partite $n$-uniform clutter $\mathcal{C}$, where every part has size $q$ and there…

Combinatorics · Mathematics 2023-06-07 Ahmad Abdi , Dabeen Lee

In this paper, we describe primary decomposition of the edge ideal of the join of some graphs in terms of that information of the edge ideal of every weighted oriented graph. Meanwhile, we also study depth and regularity of symbolic powers…

Commutative Algebra · Mathematics 2022-09-15 Yijun Cui , Guangjun Zhu , Xiaoqi Wei

Let $I(G)^{[k]}$ denote the $k$th squarefree power of the edge ideal of $G$. When $G$ is a forest, we provide a sharp upper bound for the regularity of $I(G)^{[k]}$ in terms of the $k$-admissable matching number of $G$. For any positive…

Commutative Algebra · Mathematics 2021-06-08 Nursel Erey , Takayuki Hibi

Toward a partial classification of monomial ideals with $d$-linear resolution, in this paper, some classes of $d$-uniform clutters which do not have linear resolution, but every proper subclutter of them has a $d$-linear resolution, are…

Commutative Algebra · Mathematics 2016-06-29 Marcel Morales , Ali Akbar Yazdan Pour , Rashid Zaare-Nahandi

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

We prove that, for the edge ideal of a cactus graph, the arithmetical rank is bounded above by the sum of the number of cycles and the maximum height of its associated primes. The bound is sharp, but in many cases it can be improved.…

Commutative Algebra · Mathematics 2017-03-28 Margherita Barile , Antonio Macchia

This paper presents exact formulas for the regularity and depth of powers of edge ideals of an edge-weighted star graph. Additionally, we provide exact formulas for the regularity of powers of the edge ideal of an edge-weighted integrally…

Commutative Algebra · Mathematics 2024-01-05 Guangjun Zhu , Shiya Duan , Yijun Cui , Jiaxin Li