[GAP Forum] IsConjugate() after CharacterTableDirectProduct()

[aker at gursey.gov.tr]

Dear GAP Forum,

I am trying to do some calculation with binary dihedral groups
(or Di-Cyclic groups, see  http://en.wikipedia.org/wiki/Dicyclic_group )
together with symmetric groups.

Inside my GAP code,
a function call to IsConjugate() before and after
a function call to CharacterTableDirectProduct() behaves very differently.

The first call at (1) works fine, returns false, which is the expected result.

After a call to CharacterTableDirectProduct(), the second call to  
IsConjugate() at (2) ends up in a brk>.

Could you help me with this problem?

Do I do something wrong?

Or is there a bug?

Is there a way around this problem?

Thanks a lot, have a good weekend,

k.

#### The code is given below.
#### The calls to IsConjugate() are marked (1) and (2).


## 2009-11-20

## From Wikipedia:
## Binary Dihedral Group = Di-Cyclic Group with 4m elements

f := FreeGroup( "a", "x" );

m := 4;

Dic := f/[f.1^(2*m),f.2^4,f.1^m*f.2^-2, f.1*f.2*f.1*f.2^3 ];

SetName(Dic, Concatenation( "Dic(", String(4*m), ")" ) );

Ga := Dic;

n := 2;


gensGa := GeneratorsOfGroup( Ga );





a := gensGa[1]; x:=gensGa[2];

ctGa := CharacterTable( Ga );

ctSn := CharacterTable( "Symmetric", n );


## (1) IsConjugate() works here and the result is false.

IsConjugate(Ga, One(Ga), a^6);



ctSnxGa := CharacterTableDirectProduct( ctSn, ctGa);


## (2) IsConjugate() breaks here

IsConjugate(Ga, One(Ga), a^6);


----------------------------------------------------------------
This message was sent using IMP, the Internet Messaging Program.