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Related papers: Binomial Edge Ideals of Generalized block graphs

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A set of edges $X\subseteq E(G)$ of a graph $G$ is an edge general position set if no three edges from $X$ lie on a common shortest path. The edge general position number ${\rm gp}_{\rm e}(G)$ of $G$ is the cardinality of a largest edge…

Combinatorics · Mathematics 2023-10-17 Jing Tian , Sandi Klavžar , Elif Tan

Let $G$ be a simple undirected graph. The regular number of $G$ is defined to be the minimum number of subsets into which the edge set of $G$ can be partitioned so that the subgraph induced by each subset is regular. In this work, we obtain…

Discrete Mathematics · Computer Science 2015-12-11 Ashwin Ganesan , Radha R. Iyer

Given a finite simple graph one can associate the edge ideal. In this paper we prove that a graded Betti number of the edge ideal does not vanish if the original graph contains a set of complete bipartite subgraphs with some conditions.…

Commutative Algebra · Mathematics 2014-11-05 Kyouko Kimura

When M is a finitely generated graded module over a standard graded algebra S and I is an ideal of S, it is known from work of Cutkosky, Herzog, Kodiyalam, R\"omer, Trung and Wang that the Castelnuovo-Mumford regularity of I^mM has the form…

Commutative Algebra · Mathematics 2010-12-07 David Eisenbud , Bernd Ulrich

Let $G$ be a finite simple graph and $I(G)$ denote the corresponding edge ideal. In this paper we prove that if $G$ is a very well-covered graph then for all $s \geq 2$ the regularity of $I(G)^s$ is exactly $2s+\nu(G)-1$.

Commutative Algebra · Mathematics 2019-01-03 A V Jayanthan , S Selvaraja

We calculate the minimal attached primes of the local cohomology modules of the binomial edge ideals of block graphs. In particular, we obtain a combinatorial characterisation of which of these modules are non-vanishing. We also show that…

Commutative Algebra · Mathematics 2024-12-16 David Williams

This work establishes combinatorial bounds on the Castelnuovo-Mumford regularity of edge ideals for trees and their multi-whiskered variants. For a tree \( T \), we give bounds for the Castelnuovo-Mumford regularity of \( I(T) \) in terms…

Commutative Algebra · Mathematics 2025-10-14 Ahtsham Ul Haq , Muhammad Usman Rashid , Muhammad Ishaq

We investigate the analytic spread of binomial edge ideals of finite simple graphs. We provide tight bounds for this invariant in general. For special families of graphs (e.g., closed graphs, pseudo-forests), we compute the exact value for…

Let $G$ be a finite simple graph on $n$ vertices and $J_G$ denote the corresponding binomial edge ideal in the polynomial ring $S = K[x_1, \ldots, x_n, y_1, \ldots, y_n].$ In this article, we compute the Hilbert series of binomial edge…

Commutative Algebra · Mathematics 2019-03-26 Arvind Kumar , Rajib Sarkar

Regular and distance-regular characterizations of general graphs are well-known. In particular, the spectral excess theorem states that a connected graph G is distance-regular if and only if its spectral excess (a number that can be…

Combinatorics · Mathematics 2013-09-27 A. Abiad , C. Dalfò , M. A. Fiol

Let $G$ be a simple graph with $2n$ vertices and a perfect matching. We denote by $f(G)$ and $F(G)$ the minimum and maximum forcing number of $G$, respectively. Hetyei obtained that the maximum number of edges of graphs $G$ with a unique…

Combinatorics · Mathematics 2022-11-23 Qianqian Liu , Heping Zhang

We study powers of binomial edge ideals associated with closed and block graphs.

Commutative Algebra · Mathematics 2021-07-01 Viviana Ene , Giancarlo Rinaldo , Naoki Terai

We associate to every graph a linear program for packings of vertex disjoint paths. We show that the optimal primal and dual values of the corresponding integer program are the binomial grade and height of the binomial edge ideal of the…

Commutative Algebra · Mathematics 2023-06-21 Adam LaClair

We prove that when a Lozin's transformation is applied to a graph, the (Castelnuovo-Mumford) regularity of the graph increases exactly by one, as it happens to its induced matching number. As a consequence, we show that the regularity of a…

Combinatorics · Mathematics 2013-02-14 Turker Biyikoglu , Yusuf Civan

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

Let I(G) be the edge ideal associated to a simple graph G. We study the graded Betti numbers that appear in the linear strand of the minimal free resolution of I(G).

Commutative Algebra · Mathematics 2007-05-23 Mike Roth , Adam Van Tuyl

Binomial edge ideals IG of a graph G were introduced by [4]. They found some classes of graphs G with the property that IG is a Cohen-Macaulay ideal. This might happen only for few classes of graphs. A certain generalization of being…

Commutative Algebra · Mathematics 2013-01-07 Sohail Zafar

A combinatorial property that characterizes Cohen-Macaulay binomial edge ideals has long been elusive. A recent conjecture ties the Cohen-Macaulayness of a binomial edge ideal $J_G$ to special disconnecting sets of vertices of its…

Commutative Algebra · Mathematics 2022-12-20 Davide Bolognini , Antonio Macchia , Giancarlo Rinaldo , Francesco Strazzanti

Several algebraic properties of a binomial edge ideal $J_G$ can be interpreted in terms of combinatorial properties of its associated graph $G$. In particular, the so-called cut sets of a graph $G$, special sets of vertices that disconnect…

Combinatorics · Mathematics 2025-01-30 Davide Bolognini , Antonio Macchia , Giancarlo Rinaldo , Francesco Strazzanti

We improve certain degree bounds for Grobner bases of polynomial ideals in generic position. We work exclusively in deterministically verifiable and achievable generic positions of a combinatorial nature, namely either strongly stable…

Symbolic Computation · Computer Science 2017-05-09 Amir Hashemi , Werner M. Seiler