Coverings by Few Monochromatic Pieces: A Transition Between Two Ramsey Problems

نویسندگان

  • András Gyárfás
  • Gábor N. Sárközy
  • Stanley M. Selkow
چکیده

The typical problem in (generalized) Ramsey theory is to find the order of the largest monochromatic member of a family F (for example matchings, paths, cycles, connected subgraphs) that must be present in any edge coloring of a complete graph Kn with t colors. Another area is to find the minimum number of monochromatic members of F that partition or cover the vertex set of every edge colored complete graph. Here we propose a problem that connects these areas: for a fixed positive integers s ≤ t, at least how many vertices can be covered by the vertices of no more than s monochromatic members of F in every edge coloring of Kn with t colors. Several problems and conjectures are presented, among ∗Research supported in part by the National Science Foundation under Grant No. DMS0968699.

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عنوان ژورنال:
  • Graphs and Combinatorics

دوره 31  شماره 

صفحات  -

تاریخ انتشار 2015