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Related papers: F-Purity of Binomial Edge Ideals

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We discuss algebraic and homological properties of binomial edge ideals associated to graphs which are obtained by gluing of subgraphs and the formation of cones.

Commutative Algebra · Mathematics 2012-05-03 Asia Rauf , Giancarlo Rinaldo

Consider the rational map $\phi: \mathbb{P}^{n-1}_{\mathbf k} \stackrel{[f_0:\cdots: f_n]}{\longrightarrow} \mathbb{P}^{n}_{\mathbf k}$ defined by homogeneous polynomials $f_0,\dots,f_n$ of the same degree $d$ in a polynomial ring…

Commutative Algebra · Mathematics 2019-10-31 Youngsu Kim , Vivek Mukundan

We classify the finite connected simple graphs whose edge rings are strongly Koszul. From the classification, it follows that if the edge ring is strongly Koszul, then its toric ideal possesses a quadratic Gr\"obner basis.

Commutative Algebra · Mathematics 2016-02-02 Takayuki Hibi , Kazunori Matsuda , Hidefumi Ohsugi

We give a complete characterization of graphs whose binomial edge ideal is licci. An important tool is a new general upper bound for the regularity of binomial edge ideals.

Commutative Algebra · Mathematics 2019-10-10 Viviana Ene , Giancarlo Rinaldo , Naoki Terai

We consider homogeneous binomial ideals $I=(f_1,\ldots,f_n)$ in $K[x_1, \ldots, x_n]$, where $f_i = a_i x_i^{d_i} - b_i m_i$ and $a_i \neq 0$. When such an ideal is a complete intersection, we show that the monomials which are not divisible…

Commutative Algebra · Mathematics 2024-08-09 Filip Jonsson Kling , Samuel Lundqvist , Lisa Nicklasson

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

We provide the necessary and sufficient conditions for the edge-binomials of the tree forming a $d$-sequence in terms of the degree sequence notion of a graph. We study the regularity of powers of the binomial edge ideals of trees generated…

Commutative Algebra · Mathematics 2023-05-19 Marie Amalore Nambi , Neeraj Kumar

A good edge-labeling of a graph [Ara\'ujo, Cohen, Giroire, Havet, Discrete Appl. Math., forthcoming] is an assignment of numbers to the edges such that for no pair of vertices, there exist two non-decreasing paths. In this paper, we study…

Combinatorics · Mathematics 2012-07-30 Michel Bode , Babak Farzad , Dirk Oliver Theis

For any field $\mathbb{F}$ and polynomials $f_{2},f_{3}\in\mathbb{F}[x,y]$, let $\Gamma_{\mathbb{F}}(f_{2},f_{3})$ denote the bipartite graph with vertex partition $P\cup L$, where $P$ and $L$ are two copies of $\mathbb{F}^{3}$, and…

Combinatorics · Mathematics 2020-07-31 Ming Xu , Xiaoyan Cheng , Yuansheng Tang

In this article, we compute the regularity of Rees algebra of binomial edge ideals of closed graphs. We obtain a lower bound for the regularity of Rees algebra of binomial edge ideals. We also study some algebraic properties of the Rees…

Commutative Algebra · Mathematics 2021-12-07 Arvind Kumar

Let $G$ be a simple graph with $2n$ vertices and a perfect matching. We denote by $f(G)$ and $F(G)$ the minimum and maximum forcing number of $G$, respectively. Hetyei obtained that the maximum number of edges of graphs $G$ with a unique…

Combinatorics · Mathematics 2022-11-23 Qianqian Liu , Heping Zhang

We describe the simplicial complex $\Delta$ such that the initial ideal of $J_G$ is the Stanley-Reisner ideal of $\Delta$. By $\Delta$ we show that if $J_G$ is $(S_2)$ then $G$ is accessible. We also characterize all accessible blocks with…

Commutative Algebra · Mathematics 2021-08-03 Alberto Lerda , Carla Mascia , Giancarlo Rinaldo , Francesco Romeo

In this paper, we focus on the associated primes of powers of monomial ideals and asymptotic behavior properties such as normally torsion-freeness, normality, the strong persistence property, and the persistence property. In particular, we…

Commutative Algebra · Mathematics 2024-11-22 M. Nasernejad , V. Crispin Quinonez , J. Toledo

A graph $G$ is said to be perfectly divisible if for every induced subgraph $H$ of $G$ with at least one edge, the vertex set $V(H)$ can be partitioned into two sets $A, B$ such that $H[A]$ is perfect and $\omega(B) < \omega(H)$. It is easy…

Combinatorics · Mathematics 2026-05-12 Hongzhang Chen , Kaiyang Lan , Wenlong Zhong

If $G$ is a bridgeless cubic graph, Fulkerson conjectured that we can find 6 perfect matchings (a{\em Fulkerson covering}) with the property that every edge of $G$ is contained in exactly two of them. A consequence of the Fulkerson…

Discrete Mathematics · Computer Science 2011-04-01 Jean-Luc Fouquet , Jean-Marie Vanherpe

In this paper it is shown that a sortable ideal $I$ is Freiman if and only if its sorted graph is chordal. This characterization is used to give a complete classification of Freiman principal Borel ideals and of Freiman Veronese type ideals…

Commutative Algebra · Mathematics 2019-09-25 Jürgen Herzog , Guangjun Zhu

A classical result of Nosal asserts that every $m$-edge graph with spectral radius $\lambda (G)> \sqrt{m}$ contains a triangle. A celebrated extension of Nikiforov [35] states that if $G$ is an $m$-edge graph with $\lambda (G)> \sqrt{(1-…

Combinatorics · Mathematics 2025-11-24 Yongtao Li , Hong Liu , Shengtong Zhang

In this article, we characterize all unmixed and Cohen-Macaulay parity binomial edge ideals of cactus and chordal graphs in terms of the structural properties of the graph.

Commutative Algebra · Mathematics 2026-03-18 Deblina Dey , A. V. Jayanthan , Sarang Sane

The regularity of an edge ideal of a finite simple graph $G$ is at least the induced matching number of $G$ and is at most the minimum matching number of $G$. If $G$ possesses a dominating inuduced matching, i.e., an induced matching which…

Combinatorics · Mathematics 2015-08-27 Takayuki Hibi , Akihiro Higashitani , Kyouko Kimura , Akiyoshi Tsuchiya

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…