Dear Gap Forum experts:

I have another situation in which commands that worked in Gap 3 no longer
work in Gap 4. (Again, this comes from a project being used in a first
abstract algebra course).

This works:

gap> G:=DirectProduct(DihedralGroup(8),DihedralGroup(8));
<pc group with 6 generators>
gap> C:=Centre(G);
Group([ f3, f6 ])
gap> F:=FactorGroup(G,C);
<pc group with 4 generators>

This doesn't:

gap> G:=DirectProduct(AlternatingGroup(4),DihedralGroup(4));
<group with 4 generators>
gap> C:=Centre(G);
<group with 3 generators>
gap> F:=FactorGroup(G,C);
Error no method found for operation GroupByGenerators with 2 arguments
<function>( <arguments> ) 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
brk>

How do I work around this?

Thanks for any help you can provide.

Regards,
Russell Blyth

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Russell D. Blyth                                 blythrd@slu.edu
Associate Professor                              http://sylow.slu.edu
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