Linear-bound join-transitively subnormal subgroup

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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]
If the ambient group is a finite group, this property is equivalent to the property: subnormal subgroup
View other properties finitarily equivalent to subnormal subgroup | View other variations of subnormal subgroup |
This is a variation of join-transitively subnormal subgroup|Find other variations of join-transitively subnormal subgroup |

Definition

A subgroup H of a group G is termed linear-bound join-transitively subnormal if there exists a natural number n such that, given any k-subnormal subgroup K of G, the join \langle H, K \rangle is nk-subnormal.

Here, a k-subnormal subgroup is a subgroup whose subnormal depth is at most k.

Relation with other properties

Stronger properties

Weaker properties

Metaproperties

Transitivity

NO: This subgroup property is not transitive: a subgroup with this property in a subgroup with this property, need not have the 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 subgroup properties that are not transitive|View facts related to transitivity of subgroup properties | View a survey article on disproving transitivity

This follows from the fact that normal subgroups are linear-bound join-transitively subnormal, but not all subnormal subgroups are linear-bound join-transitively subnormal. That in turn follows from the fact that subnormality is not finite-join-closed. For full proof, refer: Join of two 3-subnormal subgroups need not be subnormal, subnormality is not finite-join-closed

Template:Finite-join-closed

If H_1, H_2 \le G are both linear-bound join-transitively subnormal with corresponding natural numbers n_1, n_2, their join is linear-bound join-transitively subnormal with natural number n_1n_2. (A smaller natural number might also work for the join).