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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…

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

In this paper we study the normality of monomial ideals using linear programming and graph theory. We give normality criteria for monomial ideals, for ideals generated by monomials of degree two, and for edge ideals of graphs and clutters…

Commutative Algebra · Mathematics 2024-02-09 Luis A. Dupont , Humberto Muñoz-George , Rafael H. Villarreal

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

An ideal $I$ in a Noetherian ring is called \textit{normal} if $I^n$ is integrally closed for all $n \geq 1$. Zariski proved that in two-dimensional regular local rings, every integrally closed ideal is normal. However, in dimension three…

Commutative Algebra · Mathematics 2026-02-03 Maki Ataka , Naoyuki Matsuoka

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

Each partition $\lambda = (\lambda_1, \lambda_2, ..., \lambda_n)$ determines a so-called Ferrers tableau or, equivalently, a Ferrers bipartite graph. Its edge ideal, dubbed Ferrers ideal, is a squarefree monomial ideal that is generated by…

Commutative Algebra · Mathematics 2007-05-23 Alberto Corso , Uwe Nagel

Toric codes are obtained by evaluating rational functions of a nonsingular toric variety at the algebraic torus. One can extend toric codes to the so called generalized toric codes. This extension consists on evaluating elements of an…

Information Theory · Computer Science 2010-02-25 Diego Ruano

We show that the toric ideal of a lattice path polymatroid is generated by quadrics corresponding to symmetric exchanges, and give a monomial order under which these quadrics form a Gr\"obner basis. We then obtain an analogous result for…

Combinatorics · Mathematics 2010-06-15 Jay Schweig

We introduce and study the toric fiber product of two ideals in polynomial rings that are homogeneous with respect to the same multigrading. Under the assumption that the set of degrees of the variables form a linearly independent set, we…

Commutative Algebra · Mathematics 2007-05-23 Seth Sullivant

The toric ring together with the toric ideal arising from a nested configuration is studied, with particular attention given to the algebraic study of normality of the toric ring as well as the Gr\"obner bases of the toric ideal. One of the…

Commutative Algebra · Mathematics 2011-05-24 Hidefumi Ohsugi , Takayuki Hibi

Two correspondences have been provided that associate any linear code over a finite field with a binomial ideal. In this paper, algorithms for computing their Graver bases and universal Gr\"obner bases are given. To this end, a connection…

Commutative Algebra · Mathematics 2014-05-08 Natalia Dück , Karl-Heinz Zimmermann

We study when Taylor resolutions of monomial ideals are minimal. We consider monomial ideals with linear quotients. In particular, we determine precisely the stable ideals and the monomial ideals with linear resolutions having the miminal…

Commutative Algebra · Mathematics 2013-08-21 Munetaka Okudaira , Yukihide Takayama

We describe a generating set for the initial ideal of simplicial toric ideals with respect to the graded reverse lexicographic order, using representations of elements of affine monoids as sums of irreducible elements. Although the…

Commutative Algebra · Mathematics 2026-03-10 Ryotaro Hanyu

Statistical models of evolution are algebraic varieties in the space of joint probability distributions on the leaf colorations of a phylogenetic tree. The phylogenetic invariants of a model are the polynomials which vanish on the variety.…

Populations and Evolution · Quantitative Biology 2007-05-23 Bernd Sturmfels , Seth Sullivant

In 1980, White conjectured that the toric ideal of a matroid is generated by quadratic binomials corresponding to a symmetric exchange. In this paper, we compute Gr\"obner bases of toric ideals associated with matroids and show that, for…

Commutative Algebra · Mathematics 2020-04-28 Ken-ichi Hayase , Takayuki Hibi , Koyo Katsuno , Kazuki Shibata

Given any equigenerated monomial ideal $I$ with the property that the defining ideal $J$ of the fiber cone $ F(I)$ of $I$ is generated by quadratic binomials, we introduce a matrix such that the set of its binomial $2$-minors is a…

Commutative Algebra · Mathematics 2021-06-09 Reza Abdolmaleki , Rashid Zaare-Nahandi

We introduce a very natural topology on the set of total orderings of monomials of any algebra having a countable basis over a field. This topological space and some notable subspaces are compact. This topological framework allows us to…

Rings and Algebras · Mathematics 2011-06-02 Roberto Boldini

We study the normalization of a monomial ideal, and show how to compute its Hilbert function (using Ehrhart polynomials) if the ideal is zero dimensional. A positive lower bound for the second coefficient of the Hilbert polynomial is shown.

Commutative Algebra · Mathematics 2011-03-11 Rafael H. Villarreal

For a monomial ideal $I$, let $G(I)$ be its minimal set of monomial generators. If there is a total order on $G(I)$ such that the corresponding Lyubeznik resolution of $I$ is a minimal free resolution of $I$, then $I$ is called a Lyubeznik…

Commutative Algebra · Mathematics 2013-12-03 Jin Guo , Tongsuo Wu , Houyi Yu