Compressed Conjugacy and the Word Problem for Outer Automorphism Groups of Graph Groups

  title={Compressed Conjugacy and the Word Problem for Outer Automorphism Groups of Graph Groups},
  author={Niko Haubold and Markus Lohrey and Christian Mathissen},
  booktitle={Developments in Language Theory},
It is shown that for graph groups (right-angled Artin groups) the conjugacy problem as well as a restricted version of the simultaneous conjugacy problem can be solved in polynomial time even if input words are represented in a compressed form. As a consequence it follows that the word problem for the outer automorphism group of a graph group can be solved in polynomial time. 
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