English
Related papers

Related papers: Hilbert Coefficients and Regularity of Binomial Ed…

200 papers

The graph removal lemma is a fundamental result in extremal graph theory which says that for every fixed graph $H$ and $\varepsilon > 0$, if an $n$-vertex graph $G$ contains $\varepsilon n^2$ edge-disjoint copies of $H$ then $G$ contains…

Combinatorics · Mathematics 2023-02-01 Lior Gishboliner , Zhihan Jin , Benny Sudakov

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

Let $G$ be a complex connected reductive algebraic group that acts on a smooth complex algebraic variety $X$, and let $E$ be a $G$-equivariant algebraic vector bundle over $X$. A section of $E$ is regular if it is transversal to the zero…

Algebraic Topology · Mathematics 2021-05-06 Alexey Gorinov , Nikolay Konovalov

We consider Stanley--Reisner rings $k[x_1,...,x_n]/I(\mc{H})$ where $I(\mc{H})$ is the edge ideal associated to some particular classes of hypergraphs. For instance, we consider hypergraphs that are natural generalizations of graphs that…

Commutative Algebra · Mathematics 2015-10-12 Eric Emtander , Fatemeh Mohammadi , Somayeh Moradi

In this paper we give new upper bounds on the regularity of edge ideals whose resolutions are k-steps linear; surprisingly, the bounds are logarithmic in the number of variables. We also give various bounds for the projective dimension of…

Commutative Algebra · Mathematics 2011-10-13 Hailong Dao , Craig Huneke , Jay Schweig

Let $G$ be a connected simple graph on the vertex set $[n]$. Banerjee-Betancourt proved that $depth(S/J_G)\leq n+1$. In this article, we prove that if $G$ is a unicyclic graph, then the depth of $S/J_G$ is bounded below by $n$. Also, we…

Commutative Algebra · Mathematics 2021-12-10 Rajib Sarkar

Let $\rho_C$ be the regularity of the Hilbert function of a projective curve $C$ in $\mathbb P^n_K$ over an algebraically closed field $K$ and $\alpha_1,...,\alpha_{n-1}$ be minimal degrees for which there exists a complete intersection of…

Algebraic Geometry · Mathematics 2007-05-23 Francesca Cioffi , Maria Grazia Marinari , Luciana Ramella

In a recent paper, Caro, Lauri, Mifsud, Yuster, and Zarb ask which parameters $r$ and $c$ admit the existence of an $r$-regular graph such that the neighborhood of each vertex induces exactly $c$ edges. They show that every $r$ with $c$…

Combinatorics · Mathematics 2025-07-22 Nathan S. Sheffield , Zoe Xi

In this paper, we first give some sufficient criteria for normality of monomial ideals. As applications, we show that closed neighborhood ideals of complete bipartite graphs are normal, and hence satisfy the (strong) persistence property.…

Commutative Algebra · Mathematics 2023-08-15 Mehrdad Nasernejad , Somayeh Bandari , Leslie G. Roberts

Let $G$ be the circulant graph $C_n(S)$ with $S \subseteq \{1, 2, \dots, \lfloor \frac{n}{2} \rfloor\}$, and let $I(G)$ denote the edge ideal in the polynomial ring $R=\mathbb{K}[x_0, x_1, \dots, x_{n-1}]$ over a field $\mathbb{K}$. In this…

Combinatorics · Mathematics 2025-10-06 Sonica Anand , Amit Roy

Let X* be a subset of an affine space A^s, over a finite field K, which is parameterized by the edges of a clutter. Let X and Y be the images of X* under the maps x --> [x] and x --> [(x,1)] respectively, where [x] and [(x,1)] are points in…

Commutative Algebra · Mathematics 2013-06-24 Maria Vaz Pinto , Rafael H. Villarreal

The purpose of this paper is to study families of Artinian or one dimensional quotients of a polynomial ring $R$ with a special look to level algebras. Let $\GradAlg^H(R)$ be the scheme parametrizing graded quotients of $R$ with Hilbert…

Commutative Algebra · Mathematics 2011-11-09 Jan O. Kleppe

In this article, we give a new upper bound for the regularity of edge ideals of gap-free graphs, in terms of the their minimal triangulation. Let $H_U=G\cup F_U$ be a minimal triangulation of a gap-free graph $G$, for some maximal…

Combinatorics · Mathematics 2021-09-13 Rimpa Nandi , Ramakrishna Nanduri

We give a lower bound for the Castelnuovo-Mumford regularity of binomial edge ideals of block graphs by computing the two distinguished extremal Betti numbers of a new family of block graphs, called flower graphs. Moreover, we present a…

Commutative Algebra · Mathematics 2019-08-05 Carla Mascia , Giancarlo Rinaldo

We define the Eulerian ideal of a $k$-uniform hypergraph and study its degree and Castelnuovo--Mumford regularity. The main tool is a Gr\"obner basis of the ideal obtained combinatorially from the hypergraph. We define the notion of parity…

Commutative Algebra · Mathematics 2022-02-16 J. Neves , G. Varejão

We derive new bounds for the Castelnuovo-Mumford regularity of the ideal sheaf of a complex projective manifold of any dimension. They depend linearly on the coefficients of the Hilbert polynomial, and are optimal for rational scrolls, but…

Algebraic Geometry · Mathematics 2020-03-12 Juergen Rathmann

Sidorenko's conjecture states that, for all bipartite graphs $H$, quasirandom graphs contain asymptotically the minimum number of copies of $H$ taken over all graphs with the same order and edge density. While still open for graphs, the…

Combinatorics · Mathematics 2024-05-28 David Conlon , Joonkyung Lee , Alexander Sidorenko

In this article, we give a comprehensive survey of the recent progress of research on binomial edge ideal of a graph since 2018.

Commutative Algebra · Mathematics 2023-07-14 Priya Das

Let $G$ be a finite simple graph on the vertex set $V(G) = \{x_1, \ldots, x_n\}$ and $I(G) \subset K[V(G)]$ its edge ideal, where $K[V(G)]$ is the polynomial ring in $x_1, \ldots, x_n$ over a field $K$ with each ${\rm deg} x_i = 1$ and…

Commutative Algebra · Mathematics 2019-02-28 Takayuki Hibi , Hiroju Kanno , Kazunori Matsuda

Erd\H{o}s posed the problem of finding conditions on a graph $G$ that imply the largest number of edges in a triangle-free subgraph is equal to the largest number of edges in a bipartite subgraph. We generalize this problem to general…

Combinatorics · Mathematics 2021-02-03 Bingchen Qian , Chengfei Xie , Gennian Ge
‹ Prev 1 8 9 10 Next ›