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On the homotopy exact sequence for Noris fundamental group

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 نشر من قبل H\\'el\\`ene Esnault
 تاريخ النشر 2009
  مجال البحث
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Unlike Grothendiecks etale fundamental group, Noris fundamental group does not fulfill the homotopy exact sequence in general. We give necessary and sufficient conditions which force exactness of the sequence.

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