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Related papers: Algebraic invariants of weighted oriented graphs

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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 and $I(D)$ be its edge ideal. If $D$ contains an induced odd cycle of length $2n+1$, under certain condition we show that $ {I(D)}^{(n+1)} \neq {I(D)}^{n+1}$. We give necessary and sufficient condition…

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

Let G be a finite simple graph and let indm(G) and ordm(G) denote the induced matching number and the ordered matching number of G, respectively. We characterize all bipartite graphs G with indm(G) = ordm(G). We establish the…

Commutative Algebra · Mathematics 2025-03-28 A. V. Jayanthan , S. A. Seyed Fakhari , I. Swanson , S. Yassemi

In this paper we prove the conjectured upper bound for Castelnuovo-Mumford regularity of binomial edge ideals posed in [23], in the case of chordal graphs. Indeed, we show that the regularity of any chordal graph G is bounded above by the…

Commutative Algebra · Mathematics 2018-10-09 M. Rouzbahani Malayeri , S. Saeedi Madani , D. Kiani

In this paper we provide some precise formulas for regularity of powers of edge ideal of the disjoint union of some weighted oriented gap-free bipartite graphs. For the projective dimension of such an edge ideal, we give its exact formula.…

Commutative Algebra · Mathematics 2019-06-12 Guangjun Zhu , Li Xu , Hong Wang , Jiaqi Zhang

Let $G$ be a finite simple graph and $I(G)$ denote the corresponding edge ideal in a polynomial ring over a field $\mathbb{K}$. In this paper, we obtain upper bounds for the Castelnuovo-Mumford regularity of symbolic powers of certain…

Commutative Algebra · Mathematics 2021-08-20 Arvind Kumar , S Selvaraja

We show that the Castelnuovo-Mumford regularity of the binomial edge ideal of a graph is bounded below by the length of its longest induced path and bounded above by the number of its vertices.

Commutative Algebra · Mathematics 2012-08-14 Kazunori Matsuda , Satoshi Murai

We study the Betti numbers of binomial edge ideal associated to some classes of graphs with large Castelnuovo-Mumford regularity. As an application we give several lower bounds of the Castelnuovo-Mumford regularity of arbitrary graphs…

Commutative Algebra · Mathematics 2013-10-16 Zohaib Zahid , Sohail Zafar

We prove a conjectured upper bound for the Castelnuovo-Mumford regularity of binomial edge ideals of graphs, due to Matsuda and Murai. Indeed, we prove that $\mathrm{reg}(J_G)\leq n-1$ for any graph $G$ with $n$ vertices, which is not a…

Commutative Algebra · Mathematics 2015-04-08 Dariush Kiani , Sara Saeedi Madani

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

In this paper, we mainly study the Castelnuovo-Mumford regularity of the generalized binomial edge ideals of graphs. We show that this number can be any integer number from $2$ to $n-1$ where $n$ is the number of vertices in the underlying…

Commutative Algebra · Mathematics 2026-01-06 Dariush Kiani , Sara Saeedi Madani , Guangjun Zhu

Weighted Castelnuovo-Mumford Regularity and Weighted Global GenerationWe introduce and study a notion of Castelnuovo-Mumford regularity suitable for weighted projective spaces.

Algebraic Geometry · Mathematics 2017-12-19 F. Malaspina , G. K. Sankaran

For all integers $4 \leq r \leq d$, we show that there exists a finite simple graph $G= G_{r,d}$ with toric ideal $I_G \subset R$ such that $R/I_G$ has (Castelnuovo-Mumford) regularity $r$ and $h$-polynomial of degree $d$. To achieve this…

Commutative Algebra · Mathematics 2020-03-17 Giuseppe Favacchio , Graham Keiper , Adam Van Tuyl

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

Castelnuovo-Mumford regularity is an important invariant of projective algebraic varieties. A well known conjecture due to Eisenbud and Goto gives a bound for regularity in terms of the codimension and degree,i.e., Castelnuovo-Mumford…

Algebraic Geometry · Mathematics 2007-05-23 Sijong Kwak

Let I=I(D) be the edge ideal of a weighted oriented graph D. We determine the irredundant irreducible decomposition of I. Also, we characterize the associated primes and the unmixed property of I. Furthermore, we give a combinatorial…

Commutative Algebra · Mathematics 2020-12-08 Yuriko Pitones , Enrique Reyes , Jonathan Toledo

In this paper, we investigate the degree of $h$-polynomials of edge ideals of finite simple graphs. In particular, we provide combinatorial formulas for the degree of the $h$-polynomial for various fundamental classes of graphs such as…

Commutative Algebra · Mathematics 2024-08-26 Jennifer Biermann , Selvi Kara , Augustine O'Keefe , Joseph Skelton , Gabriel Sosa

Let $G$ be a graph and $I=I(G)$ be its edge ideal. When $G$ is the clique sum of two different length odd cycles joined at single vertex then we give an explicit description of the symbolic powers of $I$ and compute the Waldschmidt…

Commutative Algebra · Mathematics 2019-08-27 Bidwan Chakraborty , Mousumi Mandal

We present new combinatorial insights into the calculation of (Castelnuovo-Mumford) regularity of graphs.

Combinatorics · Mathematics 2015-03-23 Turker Biyikoglu , Yusuf Civan

Assume that $G$ is a graph with edge ideal $I(G)$ and matching number ${\rm match}(G)$. For every integer $s\geq 1$, we denote the $s$-th squarefree power of $I(G)$ by $I(G)^{[s]}$. It is shown that for every positive integer $s\leq {\rm…

Commutative Algebra · Mathematics 2022-07-19 S. A. Seyed Fakhari