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Related papers: Vertex cover algebras of unimodular hypergraphs

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An automorphism on a complex supermanifold $\mathcal M$ is called unipotent if it reduces to the identity on the associated graded supermanifold $gr(\mathcal M)$. These automorphisms are close to be complementary to those responsible for…

Complex Variables · Mathematics 2016-07-26 Matthias Kalus

In this work we will study the universal labeling algebra A(Gamma), a related algebra B(Gamma), and their behavior as invariants of layered graphs. We will introduce the notion of an upper vertex-like basis, which allows us to recover…

Rings and Algebras · Mathematics 2013-12-17 Susan Durst

Given a simplicial complex whose vertices are labeled with positive integers, one can associate a vector configuration whose corresponding toric variety is the Zariski closure of a hierarchical model. We classify all the vertex-weighted…

Combinatorics · Mathematics 2018-08-15 Daniel Irving Bernstein , Christopher O'Neill

A coloured graph is k-ultrahomogeneous if every isomorphism between two induced subgraphs of order at most k extends to an automorphism. A coloured graph is t-tuple regular if the number of vertices adjacent to every vertex in a set S of…

Combinatorics · Mathematics 2021-02-23 Irene Heinrich , Thomas Schneider , Pascal Schweitzer

Given a set $R$, a hypergraph is $R$-uniform if the size of every hyperedge belongs to $R$. A hypergraph $\mathcal{H}$ is called \textit{covering} if every vertex pair is contained in some hyperedge in $\mathcal{H}$. In this note, we show…

Combinatorics · Mathematics 2020-05-11 Linyuan Lu , Zhiyu Wang

In this article we study the Golod property of standard graded algebras. We show that determinantal ideals, binomial edge ideals, and permanental ideals are Golod if and only if they have a linear resolution. Next, we give a…

Commutative Algebra · Mathematics 2026-05-20 Benjamin Briggs , Trung Chau , Alessandro De Stefani

Let $n, s$ be positive integers such that $n$ is sufficiently large and $s\le n/3$. Suppose $H$ is a 3-uniform hypergraph of order $n$. If $H$ contains no isolated vertex and $deg(u)+ deg(v) > 2(s-1)(n-1)$ for any two vertices $u$ and $v$…

Combinatorics · Mathematics 2019-01-24 Yi Zhang , Yi Zhao , Mei Lu

For a simple graph $G$, assume that $J(G)$ is the vertex cover ideal of $G$ and $J(G)^{(s)}$ is the $s$-th symbolic power of $J(G)$. We prove that $(J(C)^{(s)})=(J(C)^s)$ for all $s\geq 1$ and for all odd cycle $C$. For a simplicial complex…

Commutative Algebra · Mathematics 2023-03-09 Dancheng Lu , Zexin Wang

We extend the concept of the law of a finite graph to graphings, which are, in general, infinite graphs whose vertices are equipped with the structure of a probability space. By doing this, we obtain a vast array of new unimodular measures.…

Combinatorics · Mathematics 2012-03-13 Igor Artemenko

In this article we study higher homological properties of $n$-levelled algebras and connect them to properties of the underlying graphs. Notably, to each $2$-representation-finite quadratic monomial algebra $\Lambda$ we associate a…

Representation Theory · Mathematics 2024-11-04 Karin M. Jacobsen , Mads Hustad Sandøy , Laertis Vaso

A complete classification of unimodular valuations on the set of lattice polygons with values in the spaces of polynomials and formal power series, respectively, is established. The valuations are classified in terms of their behaviour with…

Metric Geometry · Mathematics 2026-01-14 Ansgar Freyer , Monika Ludwig , Martin Rubey

Inductive algebras for the irreducible unitary representations of the universal cover of the group of unimodular two by two matrices are classified. The classification of homogeneous shift operators is obtained as a direct consequence. This…

Functional Analysis · Mathematics 2010-11-11 Amritanshu Prasad , M. K. Vemuri

An old result of M\"uller and R\"odl states that a countable graph $G$ has a subgraph whose vertices all have infinite degree if and only if for any vertex labeling of $G$ by positive integers, an infinite increasing path can be found. They…

Combinatorics · Mathematics 2022-12-06 Valentino Vito

In this paper, we continue the study of $2$-colorings in hypergraphs. A hypergraph is $2$-colorable if there is a $2$-coloring of the vertices with no monochromatic hyperedge. It is known (see Thomassen [J. Amer. Math. Soc. 5 (1992),…

Combinatorics · Mathematics 2016-11-29 Michael A Henning , Anders Yeo

We define a new combinatorial object, which we call a labeled hypergraph, uniquely associated to any square-free monomial ideal. We prove several upper bounds on the regularity of a square-free monomial ideal in terms of simple…

Commutative Algebra · Mathematics 2013-04-02 Kuei-Nuan Lin , Jason McCullough

We classify canonical algebras such that for every dimension vector of a regular module the corresponding module variety is normal (respectively, a complete intersection). We also prove that for the dimension vectors of regular modules…

Representation Theory · Mathematics 2009-09-29 Grzegorz Bobinski

In this paper we build an abstract description of vertex algebras from their basic axioms. Starting with Borcherds' notion of a vertex group, we naturally construct a family of multilinear singular maps parameterised by trees. These…

Quantum Algebra · Mathematics 2007-05-23 Craig T. Snydal

This paper is an exposition of the representation theory of vertex operator algebras in terms of associative algebras A_n(V) and their bimodules. A new result on the rationality is given. That is, a simple vertex operator algebra V is…

Quantum Algebra · Mathematics 2007-05-23 Chongying Dong , Cuipo Jiang

In this paper we give several criteria for the edge polytope of a fundamental FHM-graph to possess a regular unimodular triangulation in terms of some simple data of the the graph. We further apply our criteria to several examples of graphs…

Combinatorics · Mathematics 2016-12-02 Ginji Hamano

There is a natural infinite graph whose vertices are the monomial ideals in a polynomial ring. The definition involves Gr\"obner bases or the action of an algebraic torus. We present algorithms for computing the (affine schemes…

Commutative Algebra · Mathematics 2007-05-23 Klaus Altmann , Bernd Sturmfels