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Related papers: Toric ideals and their circuits

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Let I be the toric ideal of a homogeneous normal configuration. We prove that I is generated by circuits if and only if each unbalanced circuit of I has a "connector" which is a linear combination of circuits with a square-free term. In…

Commutative Algebra · Mathematics 2012-07-27 Jose Martinez-Bernal , Rafael H. Villarreal

In this paper, we discuss the normality of the toric rings of stable set polytopes, and the set of generators and Gr\"obner bases of toric ideals of stable set polytopes by using the results on that of edge polytopes of finite nonsimple…

Commutative Algebra · Mathematics 2019-07-12 Kazunori Matsuda , Hidefumi Ohsugi , Kazuki Shibata

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 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

Given a vertex-weighted oriented graph, we can associate to it a set of monomials. We consider the toric ideal whose defining map is given by these monomials. We find a generating set for the toric ideal for certain classes of graphs which…

Commutative Algebra · Mathematics 2021-07-12 Jennifer Biermann , Selvi Kara , Kuei-Nuan Lin , Augustine O'Keefe

A graph-theoretic method, simpler than existing ones, is used to characterize the minimal set of monomial generators for the integral closure of any algebra of polynomials generated by quadratic monomials. The toric ideal of relations…

Commutative Algebra · Mathematics 2010-01-31 Peter M. Johnson

In this article we prove that every toric ideal associated with a gap-free graph $G$ has a squarefree lexicographic initial ideal. Moreover, in the particular case when the complementary graph of $G$ is chordal (i.e. when the edge ideal of…

Commutative Algebra · Mathematics 2020-06-17 Alessio D'Alì

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

A numerical semigroup is said to be universally free if it is free for any possible arrangement of its minimal generating set. In this work, we establish that toric ideals associated with universally free numerical semigroups can be…

Commutative Algebra · Mathematics 2023-03-14 Ignacio García Marco , Pedro A. García-Sánchez , Ignacio Ojeda , Christos Tatakis

The edges of any hypergraph parametrize a monomial algebra called the edge subring of the hypergraph. We study presentation ideals of these edge subrings, and describe their generators in terms of balanced walks on hypergraphs. Our results…

Commutative Algebra · Mathematics 2013-04-23 Sonja Petrović , Despina Stasi

In the present paper, we investigate the maximal degree of minimal generators of the toric ideal of the matching polytope of a graph. It is known that the toric ideal associated to a bipartite graph is generated by binomials of degree at…

Commutative Algebra · Mathematics 2026-05-20 Kenta Mori , Ryo Motomura , Hidefumi Ohsugi , Akiyoshi Tsuchiya

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

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

In 1980, White conjectured that the toric ideal associated to a matroid is generated by binomials corresponding to a symmetric exchange. In this paper, we prove that classes of matroids for which the toric ideal is generated by quadrics and…

Combinatorics · Mathematics 2019-07-22 Kazuki Shibata

Describing families of ideals that are minimally generated by at least one, or by all, of their reduced Gr\"obner bases is a central topic in commutative algebra. In this paper, we address this problem in the context of toric ideals of…

Commutative Algebra · Mathematics 2025-04-09 Ignacio García-Marco , Irene Márquez-Corbella , Christos Tatakis

Let $G$ be a simple graph on the vertex set $\{1,\ldots,n\}$ with $m$ edges. An algebraic object attached to $G$ is the ideal $P_{G}$ generated by diagonal 2-minors of an $n \times n$ matrix of variables. In this paper we prove that if $G$…

Commutative Algebra · Mathematics 2016-07-26 Anargyros Katsabekis

Let $I_G$ be the toric ideal of a graph $G$. We characterize in graph theoretical terms the primitive, the minimal, the indispensable and the fundamental binomials of the toric ideal $I_G$.

Commutative Algebra · Mathematics 2010-02-11 Enrique Reyes , Christos Tatakis , Apostolos Thoma

We prove that the defining ideal of a sufficiently high Veronese subring of a toric algebra admits a quadratic Gr\"obner basis consisting of binomials. More generally, we prove that the defining ideal of a sufficiently high Veronese subring…

Commutative Algebra · Mathematics 2010-11-22 Takafumi Shibuta

Every normal toric ideal of codimension two is minimally generated by a Grobner basis with squarefree initial monomials. A polynomial time algorithm is presented for checking whether a toric ideal of fixed codimension is normal.

Commutative Algebra · Mathematics 2008-01-30 Pierre Dueck , Serkan Hosten , Bernd Sturmfels

Associated to any graph is a toric ideal whose generators record relations among the cuts of the graph. We study these ideals and the geometry of the corresponding toric varieties. Our theorems and conjectures relate the combinatorial…

Commutative Algebra · Mathematics 2007-05-23 Bernd Sturmfels , Seth Sullivant
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