Coxeter group

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This article defines a group property: a property that can be evaluated to true/false for any given group, invariant under isomorphism
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Definition

Symbol-free definition

A group is termed a Coxeter group if it can be equipped with a finite presentation given by the following relations:

  • The square of every generator
  • For some of the pairwise products of the generators, a certain power of that pairwise product

Definition with symbols

A group G is termed a Coxeter group if it can be equipped with a finite presentation with generators si and relations:

  • si2=1
  • (sisj)mij=1 where mij is a function of i and j (for distinct i and j)

Alternatively we can consider a matrix mij with the diagonal entries being 1 and simply require that for each i and j (not necessarily distinct) (sisj)mij=1.