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In this paper firstly, we generalize the concept of codismantlable graphs to hypergraphs and show that some special vertex decomposable hypergraphs are codismantlable. Then we generalize the concept of bouquet in graphs to hypergraphs to…

Commutative Algebra · Mathematics 2016-01-05 Fahimeh Khosh-Ahang , Somayeh Moradi

Nagel and R\"omer introduced the class of weakly vertex decomposable simplicial complexes, which include matroid, shifted, and Gorenstein complexes as well as vertex decomposable complexes. They proved that the Stanley-Reisner ideal of…

Commutative Algebra · Mathematics 2024-02-28 Patricia Klein , Matthew Koban , Jenna Rajchgot

We describe the simplicial complex $\Delta$ such that the initial ideal of $J_G$ is the Stanley-Reisner ideal of $\Delta$. By $\Delta$ we show that if $J_G$ is $(S_2)$ then $G$ is accessible. We also characterize all accessible blocks with…

Commutative Algebra · Mathematics 2021-08-03 Alberto Lerda , Carla Mascia , Giancarlo Rinaldo , Francesco Romeo

In this article, we characterize all unmixed and Cohen-Macaulay parity binomial edge ideals of cactus and chordal graphs in terms of the structural properties of the graph.

Commutative Algebra · Mathematics 2026-03-18 Deblina Dey , A. V. Jayanthan , Sarang Sane

Let $R=K[x_1,\ldots,x_n]$ be the polynomial ring in $n$ variables over a field $K$. We show that if $G$ is a connected graph with a basic $5$-cycle $C$, then $G$ is a sequentially Cohen-Macaulay graph if and only if there exists a shedding…

Commutative Algebra · Mathematics 2024-05-24 Mozhgan Koolani , Amir Mafi

Generalized diagonal matrices are matrices that have two ladders of entries that are zero in the upper right and bottom left corners. The minors of generic generalized diagonal matrices have square-free initial ideals. We give a description…

Commutative Algebra · Mathematics 2022-06-06 Vinh Nguyen , Hunter Simper

We investigate the minimal free resolutions of closed neighborhood ideals of graphs within the framework of Barile-Macchia (BM) resolutions. We show that for any tree $T$, the closed neighborhood ideal $NI(T)$ is bridge-friendly, and hence…

Commutative Algebra · Mathematics 2026-02-26 Ajay P. Joseph , Amit Roy , Anurag Singh

We characterize unmixed and Cohen-Macaulay edge-weighted edge ideals of very well-covered graphs. We also provide examples of oriented graphs which have unmixed and non-Cohen-Macaulay vertex-weighted edge ideals, while the edge ideal of…

Commutative Algebra · Mathematics 2020-03-30 Seyed Amin Seyed Fakhari , Kosuke Shibata , Naoki Terai , Siamak Yassemi

The shedding vertices of simplicial complexes are studied from an algebraic point of view. Based on this perspective, we introduce the class of ass-decomposable monomial ideals which is a generalization of the class of Stanley-Reisner…

Commutative Algebra · Mathematics 2023-05-31 Raheleh Jafari , Ali Akbar Yazdan Pour

Let $G$ be a finite simple graph and $NI(G)$ be the closed neighborhood ideal of $G$ in the polynomial ring $S=K[V(G)]$. In this paper, we study the Castelnuovo-Mumford regularity, projective dimension and Cohen-Macaulayness of this ideal.…

Commutative Algebra · Mathematics 2026-02-12 Somayeh Moradi , Leila Sharifan

We study the licci property for several classes of squarefree monomial ideals arising from graphs and related combinatorial structures. We characterize licci bi-Cohen-Macaulay squarefree monomial ideals, complementary edge ideals, $t$-path…

Commutative Algebra · Mathematics 2026-03-17 Om Prakash Bhardwaj , Trung Chau , Omkar Javadekar

In this paper we provide a full combinatorial characterization of sequentially Cohen-Macaulay binomial edge ideals of closed graphs. In addition, we show that a binomial edge ideal of a closed graph is approximately Cohen-Macaulay if and…

Commutative Algebra · Mathematics 2022-07-12 Viviana Ene , Giancarlo Rinaldo , Naoki Terai

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

Given a simplicial complex $\Delta$, we investigate how to construct a new simplicial complex $\bar{\Delta}$ such that the corresponding monomial ideals satisfy nice algebraic properties. We give a procedure to check the vertex…

Commutative Algebra · Mathematics 2023-04-25 Bijender , Ajay Kumar

Each (equigenerated) squarefree monomial ideal in the polynomial ring $S=\mathbb{K}[x_1, \ldots, x_n]$ represents a family of subsets of $[n]$, called a (uniform) clutter. In this paper, we introduce a class of uniform clutters, called…

Commutative Algebra · Mathematics 2018-07-31 Mina Bigdeli , Ali Akbar Yazdan Pour , Rashid Zaare-Nahandi

In this paper we extend one direction of Fr\"oberg's theorem on a combinatorial classification of quadratic monomial ideals with linear resolutions. We do this by generalizing the notion of a chordal graph to higher dimensions with the…

Commutative Algebra · Mathematics 2013-06-13 Emma Connon , Sara Faridi

We investigate families of two-dimensional simplicial complexes defined in terms of vertex decompositions. They include nonevasive complexes, strongly collapsible complexes of Barmak and Miniam and analogues of 2-trees of Harary and Palmer.…

Combinatorics · Mathematics 2011-02-22 Michal Adamaszek

We study the closed neighborhood ideals and the dominating ideals of graphs, in particular, of trees and cycles. We prove that the closed neighborhood ideals and the dominating ideals of trees are normally torsion-free. The closed…

Commutative Algebra · Mathematics 2022-06-17 Mehrdad Nasernejad , Ayesha Asloob Qureshi , Somayeh Bandari , Asli Musapasaouglu

Using the concept of $d$-collapsibility from combinatorial topology, we define chordal simplicial complexes and show that their Stanley-Reisner ideals are componentwise linear. Our construction is inspired by and an extension of "chordal…

Commutative Algebra · Mathematics 2018-07-26 Mina Bigdeli , Sara Faridi

Let $G$ be a finite graph and $I(G)$ its edge ideal. We give a full description of the Stanley--Reisner complex of the polarization of $I(G)^2$, naturally introducing the tools of Stanley--Reisner theory in the study of the algebraic…

Commutative Algebra · Mathematics 2026-03-10 Sara Faridi , Takayuki Hibi