Characterization of Non-minimal Tree Actions
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چکیده
Let Γ be a group acting without inversions on a tree X. If there is no proper Γ-invariant subtree, we call the action of Γ on X minimal. Here we give a characterization of non-minimal tree actions. For a non-minimal action of Γ on X, we give structure theorems for the quotient graph of groups for Γ on X, its associated edge-indexed graph and its group of deck transformations.
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تاریخ انتشار 2006