학술논문

On residually finite groups of finite general rank.
Document Type
Article
Author
Source
Mathematical Notes. Mar2017, Vol. 101 Issue 3/4, p385-390. 6p.
Subject
*FINITE groups
*SET theory
*MATHEMATICS theorems
*INTEGERS
*SUBGROUP growth
Language
ISSN
0001-4346
Abstract
Following A. I.Mal'tsev, we say that a group G has finite general rank if there is a positive integer r such that every finite set of elements of G is contained in some r-generated subgroup. Several known theorems concerning finitely generated residually finite groups are generalized here to the case of residually finite groups of finite general rank. For example, it is proved that the families of all finite homomorphic images of a residually finite group of finite general rank and of the quotient of the group by a nonidentity normal subgroup are different. Special cases of this result are a similar result of Moldavanskii on finitely generated residually finite groups and the following assertion: every residually finite group of finite general rank is Hopfian. This assertion generalizes a similarMal'tsev result on the Hopf property of every finitely generated residually finite group. [ABSTRACT FROM AUTHOR]