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Related papers: Edge ideals of some edge-weighted graphs

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We characterize unmixed and Cohen-Macaulay edge-weighted edge ideals of very well-covered graphs. We also provide examples of oriented graphs which have unmixed and non-Cohen-Macaulay vertex-weighted edge ideals, while the edge ideal of…

Commutative Algebra · Mathematics 2020-03-30 Seyed Amin Seyed Fakhari , Kosuke Shibata , Naoki Terai , Siamak Yassemi

We introduce and study the weighted $r$-path ideal of a weighted graph $G_\omega$, which is a common generalization of Conca and De Negri's $r$-path ideal for unweighted graphs and Paulsen and Sather-Wagstaff's edge ideal of the weighted…

Commutative Algebra · Mathematics 2014-08-08 Bethany Kubik , Sean Sather-Wagstaff

We provide a closed formula for the graded Betti numbers in the linear strands of all powers of binomial edge ideals $J_G$ arising from closed graphs $G$ that do not have the complete graph $K_4$ as an induced subgraph. We show that these…

Commutative Algebra · Mathematics 2026-01-19 Abbas Dohadwala , Bryan Flores-Silva , Alicia Orozco-Moya , Zoe Siegelnickel

Let $G$ be a graph on the vertex set $[n]$ and $J_G$ the associated binomial edge ideal in the polynomial ring $S=\mathbb{K}[x_1,\ldots,x_n,y_1,\ldots,y_n]$. In this paper we investigate the depth of binomial edge ideals. More precisely, we…

Commutative Algebra · Mathematics 2021-08-13 Mohammad Rouzbahani Malayeri , Sara Saeedi Madani , Dariush Kiani

To compute the local cohomology of powers of edge ideals one needs to know their saturations. The saturation of the second and third powers has been described in terms of the graph in [13] and [10]. In this article, we give a combinatorial…

Commutative Algebra · Mathematics 2015-03-10 Ha Minh Lam , Ha Thi Thu Hien

\textit{A star edge coloring} of a graph is a proper edge coloring without bichromatic paths and cycles of length four. In this paper we establish tight upper bounds for trees and subcubic outerplanar graphs, and derive an upper bound for…

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

In this article, we investigate the strongly robust property of toric ideals associated with weighted oriented graphs. We establish that the toric ideals of a broad class of monomial ideals are strongly robust; this class encompasses the…

Commutative Algebra · Mathematics 2026-02-18 Ramakrishna Nanduri , Tapas Kumar Roy

In this paper we study the Castelnuovo-Mumford regularity of the path ideals of finite simple graphs. We find new upper bounds for various path ideals of gap free graphs. In particular we prove that the path ideals of gap free and claw…

Commutative Algebra · Mathematics 2014-09-15 Arindam Banerjee

We introduce the concept of matching powers of monomial ideals. Let $I$ be a monomial ideal of $S=K[x_1,\dots,x_n]$, with $K$ a field. The $k$th matching power of $I$ is the monomial ideal $I^{[k]}$ generated by the products $u_1\cdots u_k$…

Commutative Algebra · Mathematics 2024-03-28 Nursel Erey , Antonino Ficarra

This note provides a complete solution to a certain version of the edge-isoperimetric problem for powers of a cycle graph. Namely, it shows that the maximum number of edges inside a vertex subset of $C_n^s$ of size $k$ is achieved by a set…

Combinatorics · Mathematics 2026-01-13 Kristiyan Vasilev

Let $G$ be a finite simple graph and $I(G)$ denote the corresponding edge ideal. In this paper we prove that if $G$ is a unicyclic graph then for all $s \geq 1$ the regularity of $I(G)^s$ is exactly $2s+\text{reg}(I(G))-2$. We also…

Commutative Algebra · Mathematics 2022-09-30 Ali Alilooee , Selvi Kara , S. Selvaraja

We prove that, for the edge ideal of a graph whose cycles are pairwise vertex-disjoint, the arithmetical rank is bounded above by the sum of the number of cycles and the maximum height of its associated primes.

Commutative Algebra · Mathematics 2015-11-24 Margherita Barile , Antonio Macchia

A graded ideal $I$ in $\mathbb{K}[x_1,\ldots,x_n]$, where $\mathbb{K}$ is a field, is said to have almost maximal finite index if its minimal free resolution is linear up to the homological degree $\mathrm{pd}(I)-2$, while it is not linear…

Commutative Algebra · Mathematics 2021-03-11 Mina Bigdeli

Let $G$ be a simple graph. We demonstrate a method for using $t$-admissible subgraphs of $G$ to determine the regularity of the $t$-th symbolic power of the cover ideal of $G$. As an application, we compute the regularity of powers of cover…

Commutative Algebra · Mathematics 2026-05-21 Nguyen Thu Hang , Thanh Vu

The index of a graded ideal measures the number of linear steps in the graded minimal free resolution of the ideal. In this paper we study the index of powers and squarefree powers of edge ideals. Our results indicate that the index as a…

Commutative Algebra · Mathematics 2021-03-17 Mina Bigdeli , Juergen Herzog , Rashid Zaare-Nahandi

In this paper, we characterize the Cohen-Macaulayness of the second power $I(G_\omega)^2$ of the weighted edge ideal $I(G_\omega)$ when the underlying graph $G$ is a very well-covered graph. We also characterize the Cohen-Macaulayness of…

Commutative Algebra · Mathematics 2025-02-10 Jiaxin Li , Tran Nam Trung , Guangjun Zhu

In this article, we study the linearity of the minimal free resolution of powers of facets ideals of simplicial trees. We give a complete characterization of simplicial trees for which (some) power of its facet ideal has a linear…

Commutative Algebra · Mathematics 2026-01-14 Ajay Kumar , Arvind Kumar

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

In this paper, we explain the regularity, projective dimension and depth of edge ideal of some classes of graphs in terms of invariants of graphs. We show that for a $C_5$-free vertex decomposable graph $G$, $\T{reg}(R/I(G))= c_G$, where…

Commutative Algebra · Mathematics 2017-01-24 Fahimeh Khosh-Ahang , Somayeh Moradi