, Volume 4, Issue 1, pp 71–78 | Cite as

Sparse ramsey graphs

  • Jaroslav Nešetřil
  • Vojtěch Rödl


IfH is a Ramsey graph for a graphG thenH is rich in copies of the graphG. Here we prove theorems in the opposite direction. We find examples ofH such that copies ofG do not form short cycles inH. This provides a strenghtening also, of the following well-known result of Erdős: there exist graphs with high chromatic number and no short cycles. In particular, we solve a problem of J. Spencer.

AMS subject classification (1980)

05 C 55 05 C 38 05 C 65 


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Copyright information

© Akadémiai Kiadó 1984

Authors and Affiliations

  • Jaroslav Nešetřil
    • 1
  • Vojtěch Rödl
    • 2
  1. 1.Department of CyberneticsCharles UniversityPraha 1Czechoslovakia
  2. 2.FJFI ČVUT Department of MathematicsPraha 1Czechoslovakia

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