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Related papers: The finite antichain property in Coxeter groups

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We study the existence and the distribution of "long" chains in the Weihrauch degrees, mostly focusing on chains with uncountable cofinality. We characterize when such chains have an upper bound and prove that there are no cofinal chains…

Logic · Mathematics 2026-05-07 Steffen Lempp , Alberto Marcone , Manlio Valenti

We prove that every interval order $P$ with no infinite antichain has a Gallai decomposition. That is, $P$ is a lexicographical sum of proper interval orders over a chain, an antichain or a prime interval order. This is a consequence of the…

Combinatorics · Mathematics 2024-11-12 Maurice Pouzet , Imed Zaguia

We characterize the group property of being with infinite conjugacy classes (or icc, i.e. \not= 1 and of which all conjugacy classes except 1 are infinite) for finite extensions of group.

Group Theory · Mathematics 2007-05-23 Jean-Philippe Preaux

We show that the order dimension of the weak order on a Coxeter group of type A, B or D is equal to the rank of the Coxeter group, and give bounds on the order dimensions for the other finite types. This result arises from a unified…

Combinatorics · Mathematics 2026-05-13 Nathan Reading

We show that every finitely generated Artin-Tits group admits a finite Garside family, by introducing the notion of a low element in a Coxeter group and proving that the family of all low elements in a Coxeter system (W, S) with S finite…

Group Theory · Mathematics 2014-12-01 Patrick Dehornoy , Matthew Dyer , Christophe Hohlweg

We present two results on maximal antichains in the strict chain product poset $[t_1+1]\times[t_2+1]\times\ldots\times[t_n+1]$. First, we prove that these maximal antichains are also maximum. Second, we prove that there is a bijection…

Combinatorics · Mathematics 2021-01-19 Shen-Fu Tsai

We prove that the set of permutations sorted by a stack of depth $t \geq 3$ and an infinite stack in series has infinite basis, by constructing an infinite antichain. This answers an open question on identifying the point at which, in a…

Combinatorics · Mathematics 2018-01-03 Murray Elder , Yoong Kuan Goh

In any Coxeter group, the conjugates of elements in the standard minimal generating set are called reflections and the minimal number of reflections needed to factor a particular element is called its reflection length. In this article we…

Combinatorics · Mathematics 2010-10-25 Jon McCammond , T. Kyle Petersen

We say that a finite group $G$ satisfies the independence property if, for every pair of distinct elements $x$ and $y$ of $G$, either $\{x,y\}$ is contained in a minimal generating set for $G$ or one of $x$ and $y$ is a power of the other.…

Group Theory · Mathematics 2023-05-30 Saul D. Freedman , Andrea Lucchini , Daniele Nemmi , Colva M. Roney-Dougal

Say that a finite group $G$ is mixable if a product of random elements, each chosen independently from two options, can distribute uniformly on $G$. We present conditions and obstructions to mixability. We show that $2$-groups, the…

Group Theory · Mathematics 2025-01-30 Gideon Amir , Guy Blachar , Subhajit Ghosh , Uzi Vishne

We consider a very weak chain condition for a poset, that is the absence of subsets which are order isomorphic to the set of real numbers in their natural ordering; we study generalised radical groups in which this finiteness condition is…

Group Theory · Mathematics 2023-07-18 Ulderico Dardano , Fausto De Mari

It is proven that an infinite finitely generated group cannot be elementarily equivalent to an ultraproduct of finite groups of a given Pr\"ufer rank. Furthermore, it is shown that an infinite finitely generated group of finite Pr\"ufer…

Logic · Mathematics 2018-02-27 Daniel Palacín

For Coxeter groups with sufficiently large braid relations, we prove that the sequence of powers of a Coxeter element has unbounded reflection length. We establish a connection between the reflection length functions on arbitrary Coxeter…

Group Theory · Mathematics 2024-06-11 Marco Lotz

Motivated by examples in infinite group theory, we classify the finite groups whose subgroups can never be decomposed as direct products.

Group Theory · Mathematics 2007-05-23 Ivan Marin

We show that residually finite by residually finite extensions are weakly sofic.

Group Theory · Mathematics 2019-10-22 Lev Glebsky

In this short note, we provide an inequality that holds in any finite group, only involving the orders of the elements; we prove that equality holds if and only if the group is nilpotent.

Group Theory · Mathematics 2012-12-04 Tom De Medts , Marius Tărnăuceanu

In this paper, we give the enumeration of z-classes in finite Coxeter groups.

Group Theory · Mathematics 2025-10-09 Dilpreet Kaur , Uday Bhaskar Sharma

We show that for any pair of non-trivial finite groups, their coproduct in the category of finite groups is not representable.

Group Theory · Mathematics 2017-05-12 Chris Hall

We define two different weakenings of coarse amenability (also known as Yu's property A), namely fibred coarse amenability and coarse amenability at infinity. These two properties allow us to prove that a residually finite group is coarsely…

Group Theory · Mathematics 2019-01-01 Thibault Pillon

Finite groups with very few character values are characterized. The following is the main result of this article: a finite non-abelian group has precisely four character values if and only if it is the generalized dihedral group of a…

Group Theory · Mathematics 2021-03-16 Taro Sakurai