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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

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

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

We extend the sortability concept to monomial ideals which are not necessarily generated in one degree and as an application we obtain normal Cohen-Macaulay toric rings attached to vertex cover ideals of graphs. Moreover, we consider a…

Commutative Algebra · Mathematics 2022-09-23 Jürgen Herzog , Takayuki Hibi , Somayeh Moradi

The geometric vertex decomposability property for polynomial ideals is an ideal-theoretic generalization of the vertex decomposability property for simplicial complexes. Indeed, a homogeneous geometrically vertex decomposable ideal is…

Commutative Algebra · Mathematics 2025-11-14 Mike Cummings , Sergio Da Silva , Jenna Rajchgot , Adam Van Tuyl

A toric ideal is called robust if its universal Gr\"obner basis is a minimal set of generators, and is called generalized robust if its universal Gr\"obner basis equals its universal Markov basis (the union of all its minimal sets of…

Commutative Algebra · Mathematics 2022-04-29 Christos Tatakis , Ignacio García-Marco

We study the family of graphs whose number of primitive cycles equals its cycle rank. It is shown that this family is precisely the family of ring graphs. Then we study the complete intersection property of toric ideals of bipartite graphs…

Commutative Algebra · Mathematics 2011-04-05 Isidoro Gitler , Enrique Reyes , Rafael H. Villarreal

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

We construct several pairwise-incomparable bounds on the projective dimensions of edge ideals. Our bounds use combinatorial properties of the associated graphs; in particular we draw heavily from the topic of dominating sets. Through…

Commutative Algebra · Mathematics 2011-10-25 Hailong Dao , Jay Schweig

We study the ideal of the algebraic relations among 3-point functions from a combinatorial and topological perspective. We place this problem in the broader setting of incidence toric ideals associated with incidence matrices of t-subsets…

Commutative Algebra · Mathematics 2026-05-25 Barbara Betti , Sean Grate , Thiago Holleben , Flavio Salizzoni

We explore connections between the generalized multiplicities of square-free monomial ideals and the combinatorial structure of the underlying hypergraphs using methods of commutative algebra and polyhedral geometry. For instance, we show…

Commutative Algebra · Mathematics 2020-12-22 Ali Alilooee , Ivan Soprunov , Javid Validashti

Inspired by work of Cartwright and Sturmfels, in a previous paper we introduced two classes of multigraded ideals named after them. These ideals are defined in terms of properties of their multigraded generic initial ideals. The goal of…

Commutative Algebra · Mathematics 2021-03-24 Aldo Conca , Emanuela De Negri , Elisa Gorla

Let $I_{G} \subset K[x_{1},...,x_{m}]$ be the toric ideal associated to a finite graph $G$. In this paper we study the binomial arithmetical rank and the $G$-homogeneous arithmetical rank of $I_G$ in 2 cases: $G$ is bipartite, $I_G$ is…

Commutative Algebra · Mathematics 2009-12-16 Anargyros Katsabekis

The cut polytope of a graph is an important object in several fields, such as functional analysis, combinatorial optimization, and probability. For example, Sturmfels and Sullivant showed that the toric ideals of cut polytopes are useful in…

Combinatorics · Mathematics 2020-04-13 Ryuichi Sakamoto

We study the problem when an ideal generated by adjacent 2-minors is the toric ideal of a finite graph.

Commutative Algebra · Mathematics 2014-05-15 Hidefumi Ohsugi , Takayuki Hibi

It is known that the ideals of a Leavitt path algebra $L_K(E)$ generated by $\Pl(E)$, by $\Pc(E)$ or by $\Pec(E)$ are invariant under isomorphism. Though the ideal generated by $\Pb(E)$ is not invariant we find its \lq\lq natural\rq\rq\…

Rings and Algebras · Mathematics 2020-06-24 Cristóbal Gil Canto , Dolores Martín Barquero , Cándido Martín González

In this paper we examine some natural ideal conditions and show how graphs can be defined that give a visualization of these conditions. We examine the interplay between the multiplicative ideal theory and the graph theoretic structure of…

Commutative Algebra · Mathematics 2023-03-02 Saba al-Kaseasbeh , Jim Coykendall

In the branch of mathematics known as graph theory, graphs are considered as a set of points, called vertices, with connections between these points, called edges. The purpose of this paper is to study mappings between two graphs that have…

Combinatorics · Mathematics 2019-03-19 Jeffrey Beyerl , Cameron Sharpe

Given a simple graph, consider the polynomial ring with coefficients in a field and variables identified with the edges of the graph. Given a non-empty even cardinality Eulerian subgraph and a choice of half of its edges, consider the…

Commutative Algebra · Mathematics 2023-03-06 Jorge Neves

We investigate the ideal structures of the C^*-algebras arising from topological graphs. We give the complete description of ideals of such C^*-algebras which are invariant under the so-called gauge action, and give the condition on…

Operator Algebras · Mathematics 2007-05-23 Takeshi Katsura