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Viewing Version 6 of 'locally cyclic group'
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Title of object: locally cyclic group
Canonical Name: GeneralizedCyclicGroup
Type: Definition

Created on: 2003-07-23 11:06:47
Modified on: 2003-07-24 12:56:40

Creator: yark
Modifier: yark
Author: yark

Classification: msc:20Kxx
Synonyms: locally cyclic group=locally cyclic
locally cyclic group=generalized cyclic group
locally cyclic group=generalized cyclic
locally cyclic group=generalised cyclic
locally cyclic group=generalised cyclic group

Revision comment (for changes between this and next version):

add a theorem

Preamble:

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Content:

\PMlinkescapeword{cyclic}
\PMlinkescapeword{subgroup}
\PMlinkescapeword{subgroups}
A {\em locally cyclic} (or {\em generalized cyclic}) group is a group in which any pair of elements generates a \PMlinkname{cyclic}{CyclicGroup} \PMlinkname{subgroup}{Subgroup}.
Every locally cyclic group is \PMlinkname{abelian}{AbelianGroup}.
If $G$ is a locally cyclic group, then every finite subset of $G$ generates a cyclic subgroup. Therefore, the only finitely-generated locally cyclic groups are the cyclic groups themselves. The group $(\mathbb{Q},+)$ is an example of a locally cyclic group that is not cyclic.
Subgroups and \PMlinkname{quotients}{QuotientGroup} of locally cyclic groups are also locally cyclic.