A note on central group extensions
نویسندگان
چکیده
منابع مشابه
A Note on Double Central Extensions in Exact Mal’tsev Categories
The characterisation of double central extensions in terms of commutators due to Janelidze (in the case of groups), Gran and Rossi (in the case of Mal’tsev varieties) and Rodelo and Van der Linden (in the case of semi-abelian categories) is shown to be still valid in the context of exact Mal’tsev categories.
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Let (G;N) be a pair of groups. In this article, first we con-struct a relative central extension for the pair (G;N) such that specialtypes of covering pair of (G;N) are homomorphic image of it. Second, weshow that every perfect pair admits at least one covering pair. Finally,among extending some properties of perfect groups to perfect pairs, wecharacterize covering pairs of a perfect pair (G;N)...
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ژورنال
عنوان ژورنال: Journal of the Australian Mathematical Society
سال: 1973
ISSN: 0004-9735
DOI: 10.1017/s1446788700028780