Improved bounds on the size of separators of toroidal graphs

  • L. G. Aleksandrov
  • H. N. Djidjev
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 401)


It is known that the set of vertices of any toroidal graph (graph of orientable genus 1) can be divided into two edge-disjoint sets of size no greater than 2/3 times the size of the original graph by deleting no more than √18 √n vertices [2]. The paper improves the constant before √n in the above theorem to √12 by using the structure separation graph and gives a lower bound on the optimal constant that can replace √12.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1989

Authors and Affiliations

  • L. G. Aleksandrov
    • 1
  • H. N. Djidjev
    • 1
  1. 1.Center of Informatics and Computer TechnologyBulgarian Academy of SciencesSofiaBulgaria

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