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Related papers: Bounding Betti numbers of bipartite graph ideals

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We explicitly describe cellular minimal free resolutions of certain classes of edge ideals of weighted complete bipartite graphs based on a construction of Visscher. Specifically, we show that Visscher's construction minimally resolves all…

Commutative Algebra · Mathematics 2024-07-02 Bethany Kubik , Denise Rangel Tracy , Keri Ann Sather-Wagstaff

We introduce an upper bound of the Betti numbers of a compact Riemannian manifold given integral bounds on the average of the lowest eigenvalues of the curvature operator. We then establish a new curvature condition for the Betti numbers to…

Differential Geometry · Mathematics 2022-11-11 Runze Yu

We study the dependence of graded Betti numbers of monomial ideals on the characteristic of the base field. The examples we describe include bipartite ideals, Stanley--Reisner ideals of vertex-decomposable complexes and ideals with…

Commutative Algebra · Mathematics 2010-09-23 Kia Dalili , Manoj Kummini

In this paper we study the maximum value of the largest eigenvalue for simple bipartite graphs, where the number of edges is given and the number of vertices on each side of the bipartition is given. We state a conjectured solution, which…

Combinatorics · Mathematics 2008-09-10 Amitava Bhattacharya , Shmuel Friedland , Uri N. Peled

In this paper, we deal with the signed bad number and the negative decision number of graphs. We show that two upper bounds concerning these two parameters for bipartite graphs in papers [Discrete Math. Algorithms Appl. 1 (2011), 33--41]…

Combinatorics · Mathematics 2021-02-02 Doost Ali Mojdeh , Babak Samadi

Let $G$ be a graph on the vertex set $[n]$ and $J_G$ the associated binomial edge ideal in the polynomial ring $S=\mathbb{K}[x_1,\ldots,x_n,y_1,\ldots,y_n]$. In this paper we investigate the depth of binomial edge ideals. More precisely, we…

Commutative Algebra · Mathematics 2021-08-13 Mohammad Rouzbahani Malayeri , Sara Saeedi Madani , Dariush Kiani

We compute the depth and (give bounds for) the regularity of generalized binomial edge ideals associated with generalized block graphs.

Commutative Algebra · Mathematics 2017-09-25 Faryal Chaudhry , Rida Irfan

In this paper, we establish a couple of results on extremal problems in bipartite graphs. Firstly, we show that every sufficiently large bipartite graph with average degree $D$ and with $n$ vertices on each side has a balanced independent…

Combinatorics · Mathematics 2023-06-19 Debsoumya Chakraborti

We determine (multi)graded Betti numbers of path ideals of lines and star graphs.

Commutative Algebra · Mathematics 2014-10-31 Nursel Erey

Let $G$ be a graph, and let $\lambda(G)$ denote the smallest eigenvalue of $G$. First, we provide an upper bound for $\lambda(G)$ based on induced bipartite subgraphs of $G$. Consequently, we extract two other upper bounds, one relying on…

Combinatorics · Mathematics 2024-04-16 Aryan Esmailpour , Sara Saeedi Madani , Dariush Kiani

In [{Structural properties and decomposition of linear balanced matrices}, {\it Mathematical Programming}, 55:129--168, 1992], Conforti and Rao conjectured that every balanced bipartite graph contains an edge that is not the unique chord of…

This research focuses on analyzing the depth of generalized binomial edge ideals. We extend the notion of $d$-compatible map for the pairs of a complete graph and an arbitrary graph, and using it, we give a combinatorial lower bound for the…

Commutative Algebra · Mathematics 2024-01-15 Anuvinda J , Ranjana Mehta , Kamalesh Saha

We consider the task of detecting a hidden bipartite subgraph in a given random graph. This is formulated as a hypothesis testing problem, under the null hypothesis, the graph is a realization of an Erd\H{o}s-R\'{e}nyi random graph over $n$…

Data Structures and Algorithms · Computer Science 2024-03-07 Asaf Rotenberg , Wasim Huleihel , Ofer Shayevitz

In this paper, motivated by a question posed in \cite{AH}, we introduce strongly biconvex graphs as a subclass of weakly chordal and bipartite graphs. We give a linear time algorithm to find an induced matching for such graphs and we prove…

Commutative Algebra · Mathematics 2019-05-08 Sara Saeedi Madani , Dariush Kiani

Let $G$ be a simple graph on $n$ vertices and $J_G$ denote the corresponding binomial edge ideal in $S = K[x_1, \ldots, x_n, y_1,\ldots, y_n].$ We prove that the Castelnuovo-Mumford regularity of $J_G$ is bounded above by $c(G)+1$ when $G$…

Combinatorics · Mathematics 2021-08-20 Arvind Kumar

Edge ideals of finite simple graphs are well-studied over polynomial rings. In this paper, we initiate the study of edge ideals over exterior algebras, specifically focusing on the depth and singular varieties of such ideals. We prove an…

Commutative Algebra · Mathematics 2022-08-09 Matthew Mastroeni , Jason McCullough , Andrew Osborne , Joshua Rice , Cole Willis

We study the problem of partitioning the edge set of the complete graph into bipartite subgraphs under certain constraints defined by forbidden subgraphs. These constraints lead to both classical problems, such as partitioning into…

Combinatorics · Mathematics 2025-11-26 Lajos Győrffy , András London , Gábor V. Nagy , András Pluhár

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…

For the set of graphs with a given degree sequence, consisting of any number of $2's$ and $1's$, and its subset of bipartite graphs, we characterize the optimal graphs who maximize and minimize the number of $m$-matchings. We find the…

Combinatorics · Mathematics 2008-01-16 S. Friedland , E. Krop , K. Markström

In this paper, we use Betti splittings of binomial edge ideals to establish improved upper and lower bounds for their regularity in the case of trees. As a consequence, we determine the exact regularity for certain classes of trees.

Commutative Algebra · Mathematics 2025-05-01 Rajiv Kumar , Paramhans Kushwaha