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Let $G$ be a finite connected simple graph and $I_{G}$ the toric ideal of the edge ring $K[G]$ of $G$. In the present paper, we study finite graphs $G$ with the property that $I_{G}$ is generated by quadratic binomials and $I_{G}$ possesses…

Commutative Algebra · Mathematics 2014-05-15 Takayuki Hibi , Kenta Nishiyama , Hidefumi Ohsugi , Akihiro Shikama

A signed graph is a pair $(G,\tau)$ of a graph $G$ and its sign $\tau$, where a \textit{sign} $\tau$ is a function from $\{ (e,v)\mid e\in E(G),v\in V(G), v\in e\}$ to $\{1,-1\}$. Note that graphs or digraphs are special cases of signed…

Combinatorics · Mathematics 2020-04-03 JiSun Huh , Sangwook Kim , Boram Park

We compute the graded Betti numbers for the toric ideal of a family of graphs constructed by adjoining a cycle to a complete bipartite graph. The key observation is that this family admits an initial ideal which has linear quotients. As a…

We characterize the graphs $G$ for which their toric ideals $I_G$ are complete intersections. In particular we prove that for a connected graph $G$ such that $I_G$ is complete intersection all of its blocks are bipartite except of at most…

Commutative Algebra · Mathematics 2011-10-06 Christos Tatakis , Apostolos Thoma

It has been conjectured that the toric ideal of the base ring of a discrete polymatroid is generated by symmetric exchange binomials. In the present paper, we give several classes of discrete polymatroids which yield toric ideals generated…

Commutative Algebra · Mathematics 2025-07-17 Takayuki Hibi , Seyed Amin Seyed Fakhari

In this paper, we study a class of toric ideals obtained by using some geometric data of ADE trees which are the minimal resolution graphs of rational surface singularities. We compute explicit Gr\"obner bases for these toric ideals that…

Commutative Algebra · Mathematics 2015-12-09 Gülay Kaya , Pınar Mete , Mesut Şahin

Herzog, Hibi, and Zheng classified the Cohen-Macaulay edge ideals of chordal graphs. In this paper, we classify Cohen-Macaulay edge ideals of (vertex) weighted oriented chordal and simplicial graphs, a more general class of monomial ideals.…

Commutative Algebra · Mathematics 2023-08-14 Kamalesh Saha

We investigate the structure of ideals generated by binomials (polynomials with at most two terms) and the schemes and varieties associated to them. The class of binomial ideals contains many classical examples from algebraic geometry, and…

alg-geom · Mathematics 2008-02-03 David Eisenbud , Bernd Sturmfels

In this paper, our main focus is to explore different classes of nearly normally torsion-free ideals. We first characterize all finite simple connected graphs with nearly normally torsion-free cover ideals. Next, we characterize all…

Commutative Algebra · Mathematics 2022-06-02 Mehrdad Nasernejad , Ayesha Asloob Qureshi , Kazem Khashyarmanesh , Leslie G. Roberts

B. Sturmfels and S. Sullivant associated to any graph a toric ideal, called the cut ideal. We consider monomial cut ideals and we show that their algebraic properties such as the minimal primary decomposition, the property of having a…

Commutative Algebra · Mathematics 2011-05-19 Anda Olteanu

We study the minimal homogeneous generating sets of the Eulerian ideal associated with a simple graph and its maximal generating degree. We show that the Eulerian ideal is a lattice ideal and use this to give a characterization of binomials…

Commutative Algebra · Mathematics 2024-05-24 Jorge Neves , Gonçalo Varejão

This paper studies a class of binomial ideals associated to graphs with finite vertex sets. They generalize the binomial edge ideals, and they arise in the study of conditional independence ideals. A Gr\"obner basis can be computed by…

Commutative Algebra · Mathematics 2014-06-18 Johannes Rauh

To any toric ideal $I_A$, encoded by an integer matrix $A$, we associate a matroid structure called {\em the bouquet graph} of $A$ and introduce another toric ideal called {\em the bouquet ideal} of $A$. We show how these objects capture…

Commutative Algebra · Mathematics 2017-11-08 Sonja Petrović , Apostolos Thoma , Marius Vladoiu

We give an especially simple proof of a theorem in graph theory that forms the key part of the solution to a problem in commutative algebra, on how to characterize the integral closure of a polynomial ring generated by quadratic monomials.

Commutative Algebra · Mathematics 2011-06-09 Peter M. Johnson

The universal Gr\"obner basis of an ideal is a Gr\"obner basis with respect to all term orders simultaneously. The aim of this paper is to present an algorithmic approach to compute the universal Gr\"obner basis for the toric ideal…

Commutative Algebra · Mathematics 2019-04-23 Yannis C. Stamatiou , Christos Tatakis

Let $G$ be a finite simple graph and let $I_G$ denote its associated toric ideal in the polynomial ring $R$. For each integer $n\geq 2$, we completely determine all the possible values for the tuple $({\rm reg}(R/I_G), {\rm…

Commutative Algebra · Mathematics 2023-11-17 Kieran Bhaskara , Adam Van Tuyl

In this paper, we study the componentwise linearity of edge ideals of weighted oriented graphs. We show that if $D$ is a weighted oriented graph whose edge ideal $I(D)$ is componentwise linear, then the underlying simple graph $G$ of $D$ is…

Commutative Algebra · Mathematics 2023-10-02 Manohar Kumar , Ramakrishna Nanduri , Kamalesh Saha

A connected dominating set in a graph is a dominating set of vertices that induces a connected subgraph. Following analogous studies in the literature related to independent sets, dominating sets, and total dominating sets, we study in this…

Combinatorics · Mathematics 2018-06-12 Nina Chiarelli , Martin Milanič

We determine all possible triples of depth, dimension, and regularity of edge ideals of weighted oriented graphs with a fixed number of vertices. Also, we compute all the possible Betti table sizes of edge ideals of weighted oriented trees…

Commutative Algebra · Mathematics 2025-04-18 Trung Chau , Richie Sheng , Deborah Wooton

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