Strictly characteristic not implies fully invariant: Difference between revisions

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{{subgroup property non-implication|
stronger = strictly characteristic subgroup|
weaker = fully invariant subgroup}}
==Statement==
==Statement==


A [[strictly characteristic subgroup]] of a group need not be a [[fully characteristic subgroup]].
A [[strictly characteristic subgroup]] of a group need not be a [[fully invariant subgroup]].
 
==Proof==


==Example==
{{further|[[center not is fully invariant]]}}


{{further|[[center not is fully characteristic]]}}
The [[center]] of a group is always a [[strictly characteristic subgroup]]. Thus, to show that a strictly characteristic subgroup need not be fully characteristic, it suffices to construct an example where the center is not fully characteristic. Such an example is found [[center not is fully invariant|here]].


The [[center]] of a group is always a [[strictly characteristic subgroup]]. Thus, to show that a strictly characteristic subgroup need not be fully characteristic, it suffices to construct an example where the center is not fully characteristic. Such an example is found [[center not is fully characteristic|here]].
More generally, ''any'' [[characteristic subgroup of finite group]] that is not fully invariant can work. Thus, the finite examples for [[characteristic not implies fully invariant]] all work.

Latest revision as of 04:28, 17 February 2013

This article gives the statement and possibly, proof, of a non-implication relation between two subgroup properties. That is, it states that every subgroup satisfying the first subgroup property (i.e., strictly characteristic subgroup) need not satisfy the second subgroup property (i.e., fully invariant subgroup)
View a complete list of subgroup property non-implications | View a complete list of subgroup property implications
Get more facts about strictly characteristic subgroup|Get more facts about fully invariant subgroup

EXPLORE EXAMPLES YOURSELF: View examples of subgroups satisfying property strictly characteristic subgroup but not fully invariant subgroup|View examples of subgroups satisfying property strictly characteristic subgroup and fully invariant subgroup

Statement

A strictly characteristic subgroup of a group need not be a fully invariant subgroup.

Proof

Further information: center not is fully invariant

The center of a group is always a strictly characteristic subgroup. Thus, to show that a strictly characteristic subgroup need not be fully characteristic, it suffices to construct an example where the center is not fully characteristic. Such an example is found here.

More generally, any characteristic subgroup of finite group that is not fully invariant can work. Thus, the finite examples for characteristic not implies fully invariant all work.