Frattini subgroup
From Citizendium, the Citizens' Compendium
In group theory, the Frattini subgroup is the intersection of all maximal subgroups of a group.
Formally,
where M runs over all maximal subgroups of G. If G has no maximal subgroups then
.
The Frattini is a subgroup, which is normal and indeed characteristic.
References
- Marshall Hall jr (1959). The theory of groups. New York: Macmillan, 156.

