ApCoCoA-1:Other12" groups

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Revision as of 15:49, 18 September 2013 by F lorenz (talk | contribs) (New page: === <div id="Other12_groups">Other groups</div> === ==== Description ==== This group has the following finite representation: G = <x,t | tx^{a}t^{-...)
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Description

This group has the following finite representation:

G = <x,t | tx^{a}t^{-1} = x^{b},t^{n} = 1>

for a,b >= 1 and n >= 2.

Reference

No reference available

Computation

 /*Use the ApCoCoA package ncpoly.*/
 
 // Note that a,b >= 1 and n >= 2
 MEMORY.A := 3;
 MEMORY.B := 3;
 MEMORY.N := 4;
 // x is invers to z, t has an implicit invers (Relation: t^{n} = 1)
 Use ZZ/(2)[x,t,z];
 NC.SetOrdering("LLEX");
 Define CreateRelationsOther12()
   Relations:=[];
   
   // add the invers relations xz = zx = 1
   Append(Relations,[[x,z],[1]]);
   Append(Relations,[[z,x],[1]]);
   
   // add the relation t^{n} = 1
   RelationBuffer0:=[];
   For Index0:=1 To MEMORY.N Do
     Append(RelationBuffer0,t);
   EndFor;
   Append(Relations,[RelationBuffer0,[1]]);
   
   // add the relation tx^{a}t^{-1} = x^{b}
   RelationBuffer1:=[];
   Append(RelationBuffer1,t);
   Append(RelationBuffer1,x^(MEMORY.A));
   Append(RelationBuffer1,t^(MEMORY.N-1));
   Append(Relations,[RelationBuffer1,[x^MEMORY.B]]);
   Relations;
   Return Relations;
 EndDefine;
 
 Relations:=CreateRelationsOther12();
 GB:=NC.GB(Relations,31,1,100,1000);