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Groups as automorphisms of dessins denfants

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 نشر من قبل Ruben Hidalgo
 تاريخ النشر 2021
  مجال البحث
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It is known that every finite group can be represented as the full group of automorphisms of a suitable compact dessin denfant. In this paper, we give a constructive and easy proof that the same holds for any countable group by considering non-compact dessins. Moreover, we show that any tame action of a countable group is so realizable.



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