GAP:DihedralGroup

Function type
The function takes as input a positive integer (supposed to be even) and outputs a group. An optional filter can be provided.

Behavior
The function is invoked by:

DihedralGroup([, ]n)

where $$n$$ is a positive integer. Here are the possibilities:

Related facts

 * CyclicGroup
 * AlternatingGroup
 * SymmetricGroup

Examples of usage
gap> G := DihedralGroup(8);  gap> IdGroup(G); [ 8, 3 ] gap> H := DihedralGroup(16);  gap> IsSubgroup(H,G); false gap> IsPcGroup(H); true gap> K := DihedralGroup(IsPermGroup,10); Group([ (1,2,3,4,5), (2,5)(3,4) ]) gap> Order(K); 10 gap> L := DihedralGroup(31); Error, no method found! For debugging hints type ?Recovery from NoMethodFound Error, no 2nd choice method found for `DihedralGroupCons' on 2 arguments called from DihedralGroupCons( IsPcGroup, arg[1] ) called from called from read-eval-loop Entering break read-eval-print loop ... you can 'quit;' to quit to outer loop, or you can 'return;' to continue