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Related papers: Classification of the root systems $R(m)$

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In this paper, we study the entropy of a hard random geometric graph (RGG), a commonly used model for spatial networks, where the connectivity is governed by the distances between the nodes. Formally, given a connection range $r$, a hard…

Information Theory · Computer Science 2026-01-19 Praneeth Kumar Vippathalla , Justin P. Coon , Mihai-Alin Badiu

The main result of this paper is a recursive description of all decompositions \[ \Delta^+ = \Phi_1 \sqcup \Phi_2 \sqcup \dots \sqcup \Phi_k \] of the positive roots $\Delta^+$ of an arbitrary root system $\Delta$ into a disjoint union of…

Combinatorics · Mathematics 2025-05-14 Ivan Dimitrov , Cole Gigliotti , Etan Ossip , Charles Paquette , David Wehlau

Given a crystallographic reduced root system and an element v of the lattice generated by the roots we study the minimum number |v|, called the length of v, of roots needed to express v as sum of roots. This number is related to the linear…

Combinatorics · Mathematics 2014-07-08 Rocco Chirivi'

For $0<\delta\leq 1$, let $R_k(m;\delta)$ denote the smallest $N$ such that every coloring of $k$-element subsets by two colors yields an $m$-element set $M$ with relative discrepancy $\delta$, which means that one color class has at least…

Combinatorics · Mathematics 2025-12-09 Pavel Pudlák , Vojtěch Rödl

A root system in which all roots have same norm is known as a simply laced root system. We present a simple method of classifying all simply laced root systems.

Combinatorics · Mathematics 2008-06-13 G. R. Vijayakumar

We analyze a class of spatial random spanning trees built on a realization of a homogeneous Poisson point process of the plane. This tree has a simple radial structure with the origin as its root. We first use stochastic geometry arguments…

Probability · Mathematics 2007-05-23 Francois Baccelli , Charles Bordenave

The perturbation expansion of the solution of a fixed point equation or of an ordinary differential equation may be expressed as a power series in the perturbation parameter. The terms in this series are indexed by rooted trees and depend…

Combinatorics · Mathematics 2021-03-30 William G. Faris

Results are obtained concerning the roots of asymmetric geometric representations of Coxeter groups. These representations were independently introduced by Vinberg and Eriksson, and generalize the standard geometric representation of a…

Group Theory · Mathematics 2009-12-30 Robert G. Donnelly

We generalize the definition and properties of root systems to complex reflection groups - roots become rank one projective modules over the ring of integers of a number field k. In the irreducible case, we provide a classification of root…

Representation Theory · Mathematics 2017-04-17 Michel Broué , Ruth Corran , Jean Michel

An extension of the regularized least-squares in which the estimation parameters are stretchable is introduced and studied in this paper. The solution of this ridge regression with stretchable parameters is given in primal and dual spaces…

Machine Learning · Computer Science 2018-06-12 Kar-Ann Toh , Lei Sun , Zhiping Lin

Let $p(x)$ be an integer polynomial with $m\ge 2$ distinct roots $\rho_1,\ldots,\rho_m$ whose multiplicities are $\boldsymbol{\mu}=(\mu_1,\ldots,\mu_m)$. We define the D-plus discriminant of $p(x)$ to be $D^+(p):= \prod_{1\le i<j\le…

Symbolic Computation · Computer Science 2021-05-20 Jing Yang , Chee K. Yap

In 2015 Choi, Kim, and Lovejoy studied a weighted partition function, $A_1(m)$, which counted subpartitions with a structure related to the Rogers--Ramanujan identities. They conjectured the existence of an infinite class of congruences for…

Number Theory · Mathematics 2020-04-07 Nicolas Allen Smoot

Let $G$ be a connected graph and $W$ be a set of vertices of $G$. The representation multiset of a vertex $v$ with respect to $W$, $r_m (v|W)$, is defined as a multiset of distances between $v$ and the vertices in $W$. If $r_m (u |W) \neq…

A fundamental problem in the theory of linearized and projective polynomials over finite fields is to characterize the number of roots in the coefficient field directly from the coefficients. We prove results of this type, of a recursive…

Number Theory · Mathematics 2019-04-11 Gary McGuire , John Sheekey

We propose a novel approach for studying rooted trees by using functions that we will call descent functions. We provide a construction method for rooted trees that allows to study their properties through the use of descent functions.…

Number Theory · Mathematics 2014-09-23 Marco Abrate , Stefano Barbero , Umberto Cerruti , Nadir Murru

We consider a class of quasi-integrable Hamiltonian systems obtained by adding to a non-convex Hamiltonian function of an integrable system a perturbation depending only on the angle variables. We focus on a resonant maximal torus of the…

Dynamical Systems · Mathematics 2015-06-11 Livia Corsi , Roberto Feola , Guido Gentile

This paper deals with the asymptotic statistical properties of a class of redescending M-estimators in linear models with increasing dimension. This class is wide enough to include popular high breakdown point estimators such as…

Statistics Theory · Mathematics 2016-12-20 Ezequiel Smucler

Let $d \ge 2, h \ge 1$ be integers. Using a fragmentation technique, we characterise $(h+1)$-tuples $(R_1, \dots, R_h, R)$ of non-empty families of partitions of $\{1, \dots, d\}$ such that it suffices for an order-$d$ tensor to have…

Combinatorics · Mathematics 2023-10-18 Thomas Karam

We use ergodic theoretic tools to solve a classical problem in geometric Ramsey theory. Let E be a measurable subset of R^m, with positive upper density. Let V={0,v_1,...,v_k} be a subset of R^m. We show that for r large enough, we can find…

Dynamical Systems · Mathematics 2012-01-04 Tamar Ziegler

In this paper, a linear univariate representation for the roots of a zero-dimensional polynomial equation system is presented, where the roots of the equation system are represented as linear combinations of roots of several univariate…

Symbolic Computation · Computer Science 2011-02-24 Jin-San Cheng , Xiao-Shan Gao , Leilei Guo