Nicola Sottonorcola asked:
I have to do some (simple?) computations like this with GAP:GG:=Group((1,2,4,6)(3,5,7,8), (1,3)(2,5)); H:=DirectProduct(DihedralGroup(4),DihedralGroup(4)); IsomorphicSubgroups( GG, H );
The groups are quite small:|GG|=32, |H|=16
but GAP seems very slow in doing computations like this.
The runtime of `IsomorphicSubgroups' grows with the number of generators of
the groups inolved. Thus it does not work well for $p$-groups.
It was mainly intended for groups that can be generated by 2 elements, in
particular to find (almost) simple and perfect subgroups.
> Are there a more rapid way to obtain these results?
I would compute the subgroup lattice and use `IdGroup' to determine the type
of the representatives.
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