Perfect 2-subnormal subgroup

Definition
A subgroup of a group is termed a perfect 2-subnormal subgroup if it is perfect as a group and is also a 2-subnormal subgroup.

Stronger properties

 * Weaker than::Perfect normal subgroup

Weaker properties

 * Stronger than::Perfect subnormal subgroup
 * Stronger than::Join-transitively subnormal subgroup
 * Stronger than::2-subnormal subgroup
 * Stronger than::Subnormal subgroup