Archiv der Mathematik

, Volume 94, Issue 1, pp 35–41 | Cite as

A virtually free pro-p need not be the fundamental group of a profinite graph of finite groups

  • Wolfgang HerfortEmail author
  • Pavel A. Zalesskii


A subgroup of a pro-p product with amalgamation of two p-groups is given which cannot be presented as the pro-p fundamental group of a profinite graph of p-groups.

Mathematics Subject Classification (2000)

Primary 20F18 Secondary 20E06 


Pro-p group Virtual freeness Pro-p tree 


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© Birkhäuser Verlag Basel/Switzerland 2009

Authors and Affiliations

  1. 1.University of Technology at ViennaViennaAustria
  2. 2.University of BrasiliaBrasiliaBrazil

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