Graphs, free groups and the Hanna Neumann conjecture
نویسنده
چکیده
A new bound for the rank of the intersection of finitely generated subgroups of a free group is given, formulated in topological terms, and in the spirit of Stallings [19]. The bound is a contribution to the strengthened Hanna Neumann conjecture.
منابع مشابه
Free Groups and Graphs: the Hanna Neumann Theorem
The relationship between free groups and graphs is one of the many examples of the interaction between seemingly foreign branches of mathematics. After defining and proving elementary relations between graphs and groups, this paper will present a result of Hanna Neumann on the intersection of free subgroups. Although Neumann’s orginal upper bound on the rank of the intersection has been improve...
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