Let g:=Group(....). Is there any natural way to avoid calling a procedure
checking whether h:=Subgroup(g,[...]) is indeed a subgroup in the
moment of creating h?
As we were told, this checking might be rather expensive if the
generators of h does not form a subset of g.generators.
Suppose one knows that the generators of h are words in g.generators.
Then a strange way to create h fast is to add these words into
Can it be avoided?
For instance, if g is a matrix group, there are no efficient ways to
check that h<=g, so in fact I several times ran into this problem,
when I created a subgroup of a matrix group, and
gave up without understanding what went wrong.