From expanders to better superconcentrators without cascading

  • Eli Shamir
Contibuted Papers
Part of the Lecture Notes in Computer Science book series (LNCS, volume 166)


Superconcentration is a strong property of interconnection diagraphs. We characterize its negation by existence of two disjoint and seperated sets which shrink under the forward and backward neighbor relation, respectively. This enables a better, non-cascaded design of superconcentrators, explicit ones with edge density ≤ 118, random ones with edge density ≤ 13.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1984

Authors and Affiliations

  • Eli Shamir
    • 1
  1. 1.Institut of Mathematics and Computer ScienceHebrew UniversityJerusalem

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