Sizes of Induced Subgraphs of Ramsey Graphs

نویسندگان

  • Noga Alon
  • József Balogh
  • Alexandr V. Kostochka
  • Wojciech Samotij
چکیده

An n-vertex graph G is c-Ramsey if it contains neither a complete nor an empty induced subgraph of size greater than c log n. Erdős, Faudree and Sós conjectured that every c-Ramsey graph with n vertices contains Ω(n5/2) induced subgraphs any two of which differ either in the number of vertices or in the number of edges, i.e. the number of distinct pairs (|V (H)|, |E(H)|), as H ranges over all induced subgraphs of G, is Ω(n5/2). We prove an Ω(n2.3693) lower bound.

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عنوان ژورنال:
  • Combinatorics, Probability & Computing

دوره 18  شماره 

صفحات  -

تاریخ انتشار 2009