ApCoCoA:Ikosaeder group

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Description

The Ikosaeder group has the following representation:

  I = <a,b | a^2 = b^3 = (ab)^5 = 1>

Reference

Eric W. Weisstein: Math World, Icosahedral Group

Computation

 /*Use the ApCoCoA package ncpoly.*/
 
 Use ZZ/(2)[a,b];
 NC.SetOrdering("LLEX");

 Define CreateRelationsIkosaeder()
   Relations:=[];
   // add the relation a^2 = 1 
   Append(Relations,[[a^2],[1]]);
   
   // add the relation b^3 = 1
   Append(Relations,[[b^3],[1]]);
   
   // add the relation (ab)^5 = 1
   Append(Relations,[[a,b,a,b,a,b,a,b,a,b],[1]]);
   
   Return Relations;
 EndDefine;
 
 Relations:=CreateRelationsIkosaeder();
 Gb:=NC.GB(Relations);

Example in Symbolic Data Format

 <FREEALGEBRA createdAt="2014-01-20" createdBy="strohmeier">
 	<vars>a,b</vars>
 	<basis>
 	<ncpoly>a*a-1</ncpoly>
 	<ncpoly>b*b*b-1</ncpoly>
 	<ncpoly>a*b*a*b*a*b*a*b*a*b-1</ncpoly>
 	</basis>
 	<Comment>Ikosaeder_group</Comment>
 </FREEALGEBRA>