Coset Enumeration: Difference between revisions

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== Description ==  
== Description ==  


Given a finite abstract group, enumerate the group's cosets.
Coset enumeration programs implement systematic procedures for enumerating the cosets of a subgroup H of finite index in a group G, given a set of defining relations for G and words generating H.


== Parameters ==  
== Parameters ==  


No parameters found.
$n$: number of generators
 
$g$: order of group (possibly exponential in $n$)
 
$k$: number of relations
 
$c$: maximum number of generators multiplied together in a relation


== Table of Algorithms ==  
== Table of Algorithms ==  


Currently no algorithms in our database for the given problem.
{| class="wikitable sortable"  style="text-align:center;" width="100%"
 
== Time Complexity Graph ==  


[[File:Coset Enumeration - Time.png|1000px]]
! Name !! Year !! Time !! Space !! Approximation Factor !! Model !! Reference


== Space Complexity Graph ==
|-


[[File:Coset Enumeration - Space.png|1000px]]
| [[Todd–Coxeter algorithm (Coset Enumeration Coset Enumeration)|Todd–Coxeter algorithm]] || 1936 || $O({2}^n)$ || $O(gkc)$ || Exact || Deterministic || [https://www.cambridge.org/core/journals/proceedings-of-the-edinburgh-mathematical-society/article/practical-method-for-enumerating-cosets-of-a-finite-abstract-group/0306574AD958F694A0A8339338348AA1 Time]
|-
| [[Haselgrove-Leech-Trotter (HLT) algorithm (Coset Enumeration Coset Enumeration)|Haselgrove-Leech-Trotter (HLT) algorithm]] || 1940 || $O({2}^n)$ || $O(ng)$? || Exact || Deterministic || 
|-
| [[Knuth–Bendix algorithm (Coset Enumeration Coset Enumeration)|Knuth–Bendix algorithm]] || 1970 || $O({1.5}^n n^{2} logn)$ || $O(ng)$??? || Exact || Deterministic || [https://www.cs.tufts.edu/~nr/cs257/archive/don-knuth/knuth-bendix.pdf Time]
|-
|}


== Time-Space Tradeoff ==  
== Time Complexity Graph ==  


[[File:Coset Enumeration - Pareto Frontier.png|1000px]]
[[File:Coset Enumeration - Time.png|1000px]]

Latest revision as of 09:08, 28 April 2023

Description

Coset enumeration programs implement systematic procedures for enumerating the cosets of a subgroup H of finite index in a group G, given a set of defining relations for G and words generating H.

Parameters

$n$: number of generators

$g$: order of group (possibly exponential in $n$)

$k$: number of relations

$c$: maximum number of generators multiplied together in a relation

Table of Algorithms

Name Year Time Space Approximation Factor Model Reference
Todd–Coxeter algorithm 1936 $O({2}^n)$ $O(gkc)$ Exact Deterministic Time
Haselgrove-Leech-Trotter (HLT) algorithm 1940 $O({2}^n)$ $O(ng)$? Exact Deterministic
Knuth–Bendix algorithm 1970 $O({1.5}^n n^{2} logn)$ $O(ng)$??? Exact Deterministic Time

Time Complexity Graph

Coset Enumeration - Time.png