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Mapping tori of free group automorphisms are coherent

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 نشر من قبل Mark Feighn
 تاريخ النشر 1999
  مجال البحث
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The mapping torus of an endomorphism Phi of a group G is the HNN-extension G*_G with bonding maps the identity and Phi. We show that a mapping torus of an injective free group endomorphism has the property that its finitely generated subgroups are finitely presented and, moreover, these subgroups are of finite type.



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