- Contranormal subgroup
-
In mathematics, in the field of group theory, a contranormal subgroup is a subgroup whose normal closure in the group is the whole group. Clearly, a contranormal subgroup can be normal only if it is the whole group.
Some facts:
- Every subgroup of a finite group is a contranormal subgroup of a subnormal subgroup. In general, every subgroup of a group is a contranormal subgroup of a descendant subgroup.
- Every contranormal subgroup which is also a normal subgroup, must be the whole group.
- Every abnormal subgroup is contranormal.
This algebra-related article is a stub. You can help Wikipedia by expanding it.