English
Related papers

Related papers: Binomial edge ideals and rational normal scrolls

200 papers

We will study monomial ideals $I$ in the exterior algebra as well as in the polynomial ring whose generic initial ideal is constant for all term orders up to permutations of variables. First, in the exterior algebra, we determine all graphs…

Commutative Algebra · Mathematics 2007-05-23 Satoshi Murai

Let $G_\omega$ be an edge-weighted simple graph. In this paper, we give a complete characterization of the graph $G_\omega$ whose edge ideal $I(G_\omega)$ is integrally closed. We also show that if $G_\omega$ is an edge-weighted star graph,…

Commutative Algebra · Mathematics 2023-08-14 Shiya Duan , Guangjun Zhu , Yijun Cui , Jiaxin Li

We consider the fiber cone of monomial ideals. It is shown that for monomial ideals $I\subset K[x,y]$ of height $2$, generated by $3$ elements, the fiber cone $F(I)$ of $I$ is a hypersurface ring, and that $F(I)$ has positive depth for…

Commutative Algebra · Mathematics 2019-04-11 Jürgen Herzog , Guangjun Zhu

We provide a characterisation of all graphs whose parity binomial edge ideals have pure resolutions. In particular, we show that the minimal free resolution of a parity binomial edge ideal is pure if and only if the corresponding graph is a…

Commutative Algebra · Mathematics 2020-11-17 Peter Phelan

Our main theorems provide a single geometric setting in which polynomial representatives for Schubert classes in the integral cohomology ring of the flag manifold are determined uniquely, and have positive coefficients for geometric…

Algebraic Geometry · Mathematics 2010-04-26 Allen Knutson , Ezra Miller

Let $G$ be a finite simple graph on $[n]$ and $I(G) \subset S$ the edge ideal of $G$, where $S = K[x_{1}, \ldots, x_{n}]$ is the polynomial ring over a field $K$. Let $m(G)$ denote the maximum size of matchings of $G$ and $im(G)$ that of…

Commutative Algebra · Mathematics 2014-07-23 Takayuki Hibi , Akihiro Higashitani , Kyouko Kimura , Augustine B. O'Keefe

Let $k$ be a field. We determine the ideals $I$ in a finitely generated graded $k$-algebra $A$, whose associated graded rings are isomorphic to $A$. Also we compute the graded local cohomologies of the Rees rings $A[I t]$ and give the…

Commutative Algebra · Mathematics 2007-05-23 Yukihide Takayama

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 $I=I(D)$ be the edge ideal of a weighted oriented graph $D$, let $G$ be the underlying graph of $D$, and let $I^{(n)}$ be the $n$-th symbolic power of $I$ defined using the minimal primes of $I$. We prove that $I^2=I^{(2)}$ if and only…

Commutative Algebra · Mathematics 2024-03-11 Gonzalo Grisalde , Jose Martinez-Bernal , Rafael H. Villarreal

Let $S=K[x_1, \ldots,x_n]$ denote the polynomial ring in $n$ variables over a field $K$ and $I(G) \subset S$ the edge ideal of a finite graph $G$ on $n$ vertices. Given a vector $\mathfrak{c}\in\mathbb{N}^n$ and an integer $q\geq 1$, we…

Commutative Algebra · Mathematics 2025-10-14 Takayuki Hibi , Seyed Amin Seyed Fakhari

This paper analyzes the cohomological dimension of the generalized binomial edge ideal $\calJ_{K_m,G}$ for a complete $r$-partite graph $G$. Additionally, the Krull dimension, the depth, the Castelnuovo--Mumford regularity, the Hilbert…

Commutative Algebra · Mathematics 2023-12-20 Yi-Huang Shen , Guangjun Zhu

We show that the universal Gr\"obner basis and the Graver basis of a binomial edge ideal coincide. We provide a description for this basis set in terms of certain paths in the underlying graph. We conjecture a similar result for a parity…

Commutative Algebra · Mathematics 2020-04-08 Mourtadha Badiane , Isaac Burke , Emil Sköldberg

As the binomial edge ideal of a graph is always generated by homogeneous quadratic polynomials corresponding to the edges of the graph, the question of when a binomial edge ideal defines a Koszul algebra has been studied by many authors…

Commutative Algebra · Mathematics 2026-01-22 Adam LaClair , Matthew Mastroeni , Jason McCullough , Irena Peeva

Powers of (monomial) ideals is a subject that still calls attraction in various ways. Let $I\subset \mathbb K[x_1,\ldots,x_n]$ be a monomial ideal and let $G(I)$ denote the (unique) minimal monomial generating set of $I$. How small can…

Commutative Algebra · Mathematics 2019-09-02 Oleksandra Gasanova

Let $I$ be a monomial ideal of a polynomial ring $R=K[x_1,\ldots,x_n]$ over a field $K$ and let ${\rm sgn}(I)$ be its signature ideal. If $I$ is not a principal ideal, we show that the depth of $R/I$ is the depth of $R/{\rm sgn}(I)$, and…

Commutative Algebra · Mathematics 2026-01-07 Jovanny Ibarguen , Carlos E. Valencia , Rafael H. Villarreal

In this paper we prove the conjectured upper bound for Castelnuovo-Mumford regularity of binomial edge ideals posed in [23], in the case of chordal graphs. Indeed, we show that the regularity of any chordal graph G is bounded above by the…

Commutative Algebra · Mathematics 2018-10-09 M. Rouzbahani Malayeri , S. Saeedi Madani , D. Kiani

Let $\KX =K\langle X_1,\ldots ,X_n\rangle$ be the free algebra generated by $X=\{ X_1,\ldots ,X_n\}$ over a field $K$. It is shown that with respect to any weighted $\mathbb{N}$-gradation attached to $\KX$, minimal homogeneous generating…

Rings and Algebras · Mathematics 2015-06-22 Huishi Li

We show that for a vertex decomposable simplicial complex $\Delta$, the Rees algebra of $I_{\Delta^{\vee}}$ is a normal Cohen-Macaulay domain. As consequences, we show that any squarefree weakly polymatroidal ideal is normal and we obtain…

Commutative Algebra · Mathematics 2023-11-28 Somayeh Moradi

To any lattice $L \subset \mathbb{Z}^{m}$ one can associate the lattice ideal $I_{L} \subset K[x_{1},...,x_{m}]$. This paper concerns the study of the relation between the binomial arithmetical rank and the minimal number of generators of…

Commutative Algebra · Mathematics 2013-04-29 Anargyros Katsabekis

In this article, we explore the class of graphs for which the projective dimension of the quotient of the binomial edge ideals matches the big height of that ideal. Additionally, we investigate the Vasconcelos number of binomial edge ideals…

Commutative Algebra · Mathematics 2025-08-19 Arvind Kumar , Joshua Pomeroy , Le Tran