Dear Forum,

vahid Dabbaghianabdoly wrote:

When I want to get the conjugacy classes subgroups of the Alternating
group on 11 elements, after about one hour I get the following message
and I should close the gap and open it again to use it.
I do appreciate if you let me know how can fix it.

gap> g:=AlternatingGroup(11);
Alt( [ 1 .. 11 ] )
gap> ConjugacyClassesSubgroups(g);
gap: cannot extend the workspace any more

Well, extrapolating runtimes for alternating groups of smaller degrees,
I would predict that this would need several hours on a `usual' PC,
provided that enough memory is available.
If you don't have enough (where I cannot easily give a reasonable estimate
for what is `enough' here), I would suggest rather to use the transitive groups library,
and to construct your groups from there (surely, this is some work, since you have
to form direct products and to check which of the conjugates of the considered groups
under the symmetric group are not conjugate in the alternating group).
The description of the transitive groups library can be found in the chapter
about group libraries in the reference manual.

Hope this helps,

Stefan Kohl