On certain varieties of groups which are central extensions
نویسندگان
چکیده
منابع مشابه
Central Extensions in Mal’tsev Varieties
We show that every algebraically–central extension in a Mal’tsev variety — that is, every surjective homomorphism f : A−→ B whose kernel–congruence is contained in the centre of A, as defined using the theory of commutators — is also a central extension in the sense of categorical Galois theory; this was previously known only for varieties of Ω-groups, while its converse is easily seen to hold ...
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An extension of a group A by a group G is thought of here simply as a group H containing A as a normal subgroup with quotient H/A isomorphic to G. It is called a central Frattini extension if A is contained in the intersection of the centre and the Frattini subgroup of H . The result of the paper is that, given a finite abelian A and finite G, there exists a central Frattini extension of A by G...
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ژورنال
عنوان ژورنال: Journal of the Australian Mathematical Society. Series A. Pure Mathematics and Statistics
سال: 1984
ISSN: 0263-6115
DOI: 10.1017/s1446788700022333