[GAP Forum] Why is following error coming

[Vipul Kakkar]

Dear Members

I am trying following calculation in GAP
 f:=FreeGroup(3);
g:=f/[f.1^7,f.2^7,f.3^(7^3),f.1^-1*f.2^-1*f.1*f.2*(f.3^-1)^49,f.1^-1*f.3^-1*f.1*f.3,f.2^-1*f.3^-1*f.2*f.3];

The order of g is 7^5. I tried to find the maximal subgroups or all
Subgroups of g, but I get following error

Error, the coset enumeration has defined more than 16384000 cosets
 called from
TCENUM.CosetTableFromGensAndRels( fgens, grels, fsgens ) called from
CosetTableFromGensAndRels( fgens, grels, fsgens ) called from
TryCosetTableInWholeGroup( H ) called from
CosetTableInWholeGroup( H ) called from
IndexInWholeGroup( H ) called from
...  at line 8 of *stdin*
type 'return;' if you want to continue with a new limit of 32768000 cosets,
type 'quit;' if you want to quit the coset enumeration,
type 'maxlimit := 0; return;' in order to continue without a limit

Why is it coming?
How can I get rid of this situation and how to find them?


with regards

Vipul Kakkar