Left-transitively fixed-depth subnormal subgroup: Difference between revisions

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* [[Stronger than::Subnormal subgroup]]: {{proofat|[[Normal not implies left-transitively fixed-depth subnormal]]}}
* [[Stronger than::Subnormal subgroup]]: {{proofat|[[Normal not implies left-transitively fixed-depth subnormal]]}}
===Related properties===
* [[Right-transitively fixed-depth subnormal subgroup]]


==Metaproperties==
==Metaproperties==

Revision as of 12:39, 27 March 2009

BEWARE! This term is nonstandard and is being used locally within the wiki. [SHOW MORE]

This article defines a subgroup property: a property that can be evaluated to true/false given a group and a subgroup thereof, invariant under subgroup equivalence. View a complete list of subgroup properties[SHOW MORE]

Definition

A subgroup H of a group K is termed left-transitively fixed-depth subnormal in K if there exists a natural number k1 such that H is left-transitively k-subnormal in K. In other words, whenever K is a k-subnormal subgroup of a group G, H is also k-subnormal in G.

Note that any subgroup that is left-transitively k-subnormal is also left-transitively l-subnormal for lk.

Relation with other properties

Stronger properties

Weaker properties

Related properties

Metaproperties

Transitivity

This subgroup property is transitive: a subgroup with this property in a subgroup with this property, also has this property in the whole group.
ABOUT THIS PROPERTY: View variations of this property that are transitive | View variations of this property that are not transitive
ABOUT TRANSITIVITY: View a complete list of transitive subgroup properties|View a complete list of facts related to transitivity of subgroup properties |Read a survey article on proving transitivity

If HKG are such that H is left-transitively k-subnormal in K and K is left-transitively l-subnormal in G, then H is left-transitively max{k,l}-subnormal in G.

Intersection-closedness

This subgroup property is finite-intersection-closed; a finite (nonempty) intersection of subgroups with this property, also has this property
View a complete list of finite-intersection-closed subgroup properties

An intersection of finitely many such subgroups again has the property. In particular, the intersection of a left-transitively k-subnormal subgroup and a left-transitively l-subnormal subgroup is left-transitively max{k,l}-subnormal.

Trimness

This subgroup property is trim -- it is both trivially true (true for the trivial subgroup) and identity-true (true for a group as a subgroup of itself).
View other trim subgroup properties | View other trivially true subgroup properties | View other identity-true subgroup properties

Template:Finite-join-closed

A join of finitely many such subgroups again has the property. In particular, the join of a left-transitively k-subnormal subgroup and a left-transitively l-subnormal subgroup is left-transitively max{k,l}-subnormal.