, Volume 9, Issue 3, pp 245–253 | Cite as

The size of chordal, interval and threshold subgraphs

  • P. Erdös
  • A. Gyárfás
  • E. T. Ordman
  • Y. Zalcstein


Given a graphG withn vertices andm edges, how many edges must be in the largest chordal subgraph ofG? Form=n2/4+1, the answer is 3n/2−1. Form=n2/3, it is 2n−3. Form=n2/3+1, it is at least 7n/3−6 and at most 8n/3−4. Similar questions are studied, with less complete results, for threshold graphs, interval graphs, and the stars on edges, triangles, andK4's.

AMS subject classification (1980)

05 C 35 


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Copyright information

© Akadémiai Kiadó 1989

Authors and Affiliations

  • P. Erdös
    • 1
  • A. Gyárfás
    • 2
  • E. T. Ordman
    • 3
  • Y. Zalcstein
    • 4
  1. 1.Mathematical InstituteHungarian Academy of SciencesHungary
  2. 2.Automata Theory Research GroupHungarian Academy of SciencesHungary
  3. 3.Department of Mathematical SciencesMemphis State UniversityUSA
  4. 4.Division of Computer and Computation ResearchNational Science FoundationWashington, DCUSA

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