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Related papers: Binomial edge ideals of cographs

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In this article, we obtain an upper bound for the regularity of the binomial edge ideal of a graph whose every block is either a cycle or a clique. As a consequence, we obtain an upper bound for the regularity of binomial edge ideal of a…

Commutative Algebra · Mathematics 2020-10-23 A. V. Jayanthan , Rajib Sarkar

Castelnuovo-Mumford regularity is a measure of algebraic complexity of an ideal. Regularity of monomial ideals can be investigated combinatorially. We use a simple graph decomposition and results from structural graph theory to prove,…

Commutative Algebra · Mathematics 2020-07-07 Grigoriy Blekherman , Jaewoo Jung

We study the regularity of binomial edge ideals. For a closed graph $G$ we show that the regularity of the binomial edge ideal $J_G$ coincides with the regularity of $\ini_{\lex}(J_G)$ and can be expressed in terms of the combinatorial data…

Commutative Algebra · Mathematics 2013-07-09 Viviana Ene , Andrei Zarojanu

In a 2008 paper, the first author and Van Tuyl proved that the regularity of the edge ideal of a graph G is at most one greater than the matching number of G. In this note, we provide a generalization of this result to any square-free…

Combinatorics · Mathematics 2016-11-17 Huy Tài Hà , Russ Woodroofe

Let $G$ be the circulant graph $C_n(S)$ with $S\subseteq\{ 1,\ldots,\left \lfloor\frac{n}{2}\right \rfloor\}$ and let $I(G)$ be its edge ideal in the ring $K[x_0,\ldots,x_{n-1}]$. Under the hypothesis that $n$ is prime we : 1) compute the…

Commutative Algebra · Mathematics 2017-06-07 Giancarlo Rinaldo

A famous theorem of Kalai and Meshulam is that $\mathrm{reg}(I + J) \leq \mathrm{reg}(I) + \mathrm{reg}(J) -1$ for any squarefree monomial ideals $I$ and $J$. This result was subsequently extended by Herzog to the case where $I$ and $J$ are…

Commutative Algebra · Mathematics 2024-05-24 Adam LaClair

We study chains of nonzero edge ideals that are invariant under the action of the monoid $\mathrm{Inc}$ of increasing functions on the positive integers. We prove that the sequence of Castelnuovo--Mumford regularity of ideals in such a…

Commutative Algebra · Mathematics 2023-01-31 Do Trong Hoang , Hop D. Nguyen , Quang Hoa Tran

We study the asymptotic behavior of the Castelnuovo-Mumford regularity along chains of graded ideals in increasingly larger polynomial rings that are invariant under the action of symmetric groups. A linear upper bound for the regularity of…

Commutative Algebra · Mathematics 2020-09-09 Dinh Van Le , Uwe Nagel , Hop D. Nguyen , Tim Roemer

We study the Castelnuovo-Mumford regularity of powers of edge ideals. We prove that if G is a bipartite graph, then reg(I(G)^s) \leq 2s + reg I(G) - 2 for all s \geq 2, which is the best possible upper bound for any s. Suspension plays a…

Commutative Algebra · Mathematics 2019-09-06 Arindam Banerjee , Eran Nevo

Let $G$ be a finite simple graph. We give a lower bound for the Castelnuovo-Mumford regularity of the toric ideal $I_G$ associated to $G$ in terms of the sizes and number of induced complete bipartite graphs in $G$. When $G$ is a chordal…

Commutative Algebra · Mathematics 2016-05-24 Jennifer Biermann , Augustine O'Keefe , Adam Van Tuyl

In this article, we prove that for several classes of graphs, the Castelnuovo-Mumford regularity of symbolic powers of their edge ideals coincide with that of their ordinary powers.

Commutative Algebra · Mathematics 2019-12-17 A. V. Jayanthan , Rajiv Kumar

We obtain an improved lower bound for the regularity of the binomial edge ideals of trees. We prove an upper bound for the regularity of the binomial edge ideals of certain subclass of block-graphs. As a consequence we obtain sharp upper…

Commutative Algebra · Mathematics 2018-04-30 A. V. Jayanthan , N. Narayanan , B. V. Raghavendra Rao

We give a complete characterization of graphs whose binomial edge ideal is licci. An important tool is a new general upper bound for the regularity of binomial edge ideals.

Commutative Algebra · Mathematics 2019-10-10 Viviana Ene , Giancarlo Rinaldo , Naoki Terai

We give a bound on the Castelnuovo-Mumford regularity of a homogeneous ideals I, in a polynomial ring A, in terms of number of variables and the degrees of generators, when the dimension of A/I is at most two. This bound improves the one…

Commutative Algebra · Mathematics 2007-05-23 Marc Chardin , Amadou Lamine Fall

For any two integers $d,r \geq 1$, we show that there exists an edge ideal $I(G)$ such that the ${\rm reg}\left(R/I(G)\right)$, the Castelnuovo-Mumford regularity of $R/I(G)$, is $r$, and ${\rm deg} (h_{R/I(G)}(t))$, the degree of the…

Commutative Algebra · Mathematics 2018-10-17 Takayuki Hibi , Kazunori Matsuda , Adam Van Tuyl

We study the topology of the lcm-lattice of edge ideals and derive upper bounds on the Castelnuovo-Mumford regularity of the ideals. In this context it is natural to restrict to the family of graphs with no induced 4-cycle in their…

Combinatorics · Mathematics 2009-09-16 Eran Nevo

We survey recent studies on the Castelnuovo-Mumford regularity of edge ideals of graphs and their powers. Our focus is on bounds and exact values of $\text{reg} I(G)$ and the asymptotic linear function $\text{reg} I(G)^q$, for $q \geq 1,$…

Commutative Algebra · Mathematics 2022-09-28 Arindam Banerjee , Selvi Kara , Huy Tai Ha

Let $G$ be a simple graph on $n$ vertices and $\mathcal{I}_G$ denotes parity binomial edge ideal of $G$ in the polynomial ring $S = \mathbb{K}[x_1,\ldots, x_n, y_1, \ldots, y_n].$ We obtain a lower bound for the regularity of parity…

Commutative Algebra · Mathematics 2021-08-20 Arvind Kumar

Since the introduction of binomial edge ideals $J_{G}$ by Herzog et al. and independently Ohtani, there has been significant interest in relating algebraic invariants of the binomial edge ideal with combinatorial invariants of the…

Commutative Algebra · Mathematics 2025-03-24 Adam LaClair

Let $G$ be a simple graph on $n$ vertices, and let $J_G$ denotes the corresponding binomial edge ideal in $S=\mathbb{K}[x_1,\ldots,x_n,y_1,\ldots,y_n]$, where $\mathbb{K}$ is a field. We show that if a vertex satisfies a certain degree…

Commutative Algebra · Mathematics 2025-12-03 Kanoy Kumar Das , Rajiv Kumar , Paramhans Kushwaha