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In this paper, we introduce some reduction processes on graphs which preserve the regularity of related edge ideals. As a consequence, an alternative proof for the theorem of R. Fr\"oberg on linearity of resolution of edge ideal of graphs…

Commutative Algebra · Mathematics 2015-07-28 Marcel Morales , Ali Akbar Yazdan Pour , Rashid Zaare-Nahandi

Inspired by the definition of $\bf{t}$-spread monomial ideals, in this paper, we introduce $\bf{t}$-spread $d$-partite hypergraph $K^{\bf t}_V$ and study its edge ideal $I(K^{\bf t}_V)$. We prove that $I(K^{\bf t}_V)$ has linear quotients,…

Commutative Algebra · Mathematics 2023-08-08 Aslı Musapaşaoğlu , Mehrdad Nasernejad , Ayesha Asloob Qureshi

Let $G_\omega$ be an edge-weighted simple graph. In this paper, we give a complete characterization of the graph $G_\omega$ whose edge ideal $I(G_\omega)$ is integrally closed. We also show that if $G_\omega$ is an edge-weighted star graph,…

Commutative Algebra · Mathematics 2023-08-14 Shiya Duan , Guangjun Zhu , Yijun Cui , Jiaxin Li

Let $G$ be a finite graph allowing loops, having no multiple edge and no isolated vertex. We associate $G$ with the edge polytope ${\cal P}_G$ and the toric ideal $I_G$. By classifying graphs whose edge polytope is simple, it is proved that…

Commutative Algebra · Mathematics 2018-08-22 Hidefumi Ohsugi , Takayuki Hibi

We investigate the analytic spread of binomial edge ideals of finite simple graphs. We provide tight bounds for this invariant in general. For special families of graphs (e.g., closed graphs, pseudo-forests), we compute the exact value for…

The celebrated Mantel's theorem states that any triangle-free graph on $n$ vertices contains at most $\left\lfloor n^2/4\right\rfloor$ edges. It is natural to ask how many triangles must exist in a graph with more than $\left\lfloor…

Combinatorics · Mathematics 2026-02-27 Yuhang Bai , Gyula O. H. Katona , Zixuan Yang

In this paper, we introduce and study families of squarefree monomial ideals called clique ideals and independence ideals that can be associated to a finite graph. A family of clique ideals with linear resolutions has been characterized.…

Commutative Algebra · Mathematics 2017-12-05 Somayeh Moradi

We introduce and study the concept which we call the splitting of a graph and compare algebraic properties of the edge ideals of graphs and those of their splitting graphs.

Commutative Algebra · Mathematics 2019-08-27 Jürgen Herzog , Somayeh Moradi , Masoomeh Rahimbeigi

Nearly complete intersection ideals were introduced by A. Boocher and J. Seiner (2018) and defines a special class of monomial ideals in a polynomial ring. These ideals were used to give a lower bound of the total sum of betti numbers that…

Commutative Algebra · Mathematics 2021-01-21 Charlie Miller , Branden Stone

We introduce the concept of $t$-spread monomials and $t$-spread strongly stable ideals. These concepts are a natural generalization of strongly stable and squarefree strongly stable ideals. For the study of this class of ideals we use the…

Commutative Algebra · Mathematics 2018-06-05 Viviana Ene , Jürgen Herzog , Ayesha Asloob Qureshi

The distance ideals of graphs are algebraic invariants that generalize the Smith normal form (SNF) and the spectrum of several distance matrices associated with a graph. In general, distance ideals are not monotone under taking induced…

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…

Let $I(G)$ be the edge ideal of a simple graph $G$. We prove that $I(G)^2$ has a linear free resolution if and only if $G$ is gap-free and reg$I(G) \le 3$. Similarly, we show that $I(G)^3$ has a linear free resolution if and only if $G$ is…

Commutative Algebra · Mathematics 2022-10-11 Nguyen Cong Minh , Thanh Vu

We prove two recent conjectures on some upper bounds for the Castelnuovo-Mumford regularity of the binomial edge ideals of some different classes of graphs. We prove the conjecture of Matsuda and Murai for graphs which has a cut edge or a…

Commutative Algebra · Mathematics 2013-11-19 Dariush Kiani , Sara Saeedi Madani

A good edge-labelling of a simple graph is a labelling of its edges with real numbers such that, for any ordered pair of vertices (u,v), there is at most one nondecreasing path from u to v. Say a graph is good if it admits a good…

Combinatorics · Mathematics 2012-11-13 Abbas Mehrabian

We study the homological algebra of edge ideals of Erd\"{o}s-R\'enyi random graphs. These random graphs are generated by deleting edges of a complete graph on $n$ vertices independently of each other with probability $1-p$. We focus on some…

Combinatorics · Mathematics 2021-05-05 Arindam Banerjee , D. Yogeshwaran

We introduce a class of ideals generated by a set of 2-minors of $m\times n$-matrix of indeterminates indexed by a pair of graphs. This class of ideals is a natural common generalization of binomial edge ideals and ideals generated by…

Commutative Algebra · Mathematics 2015-01-14 Viviana Ene , Jürgen Herzog , Takayuki Hibi , Ayesha Asloob Qureshi

We bring additional support to the conjecture saying that a rational cuspidal plane curve is either free or nearly free. This conjecture was confirmed for curves of even degree, and in this note we prove it for many odd degrees. In…

Algebraic Geometry · Mathematics 2019-09-17 Alexandru Dimca , Gabriel Sticlaru

The $t$-connected ideal of a graph $G$ is generated by all connected induced subgraphs of $G$ with $t$ vertices. When $t = 2$, this coincides with the usual edge ideal of the graph. Following the work of Faridi et al., we give a…

Commutative Algebra · Mathematics 2025-12-09 Trung Chau , Richie Sheng , Tim Tribone , Deborah Wooton

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