, Volume 9, Issue 1, pp 9–19 | Cite as

On 3-pushdown graphs with large separators

  • Z. Galil
  • R. Kannan
  • E. Szemerédi


For an integers letl s (n), thes-iterated logarithm function, be defined inductively:l0(n)=n,ls+1(n)=log2 (l2(n)) fors≧0. We show that for every fixeds and alln large enough, there is ann-vertex 3-pushdown graph whose smallest separator contains at leastΩ(n/l s (n)) vertices.

AMS subject classification (1980)

05C35 68C25 68C40 


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Copyright information

© Akadémiai Kiadó 1989

Authors and Affiliations

  • Z. Galil
    • 1
    • 2
  • R. Kannan
    • 3
    • 4
  • E. Szemerédi
    • 5
  1. 1.Columbia UniversityUSA
  2. 2.Tel-Aviv UniversityIsrael
  3. 3.University of ChicagoUSA
  4. 4.Hungarian Academy of SciencesHungary
  5. 5.Carnegie Mellon UniversityUSA

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