Erdös-Ko-Rado and Hilton-Milner Type Theorems for Intersecting Chains in Posets

نویسندگان

  • Péter L. Erdös
  • Ákos Seress
  • László A. Székely
چکیده

We prove Erdős-Ko-Rado and Hilton-Milner type theorems for t-intersecting k-chains in posets using the kernel method. These results are common generalizations of the original EKR and HM theorems, and our earlier results for intersecting k-chains in the Boolean algebra. For intersecting k-chains in the c-truncated Boolean algebra we also prove an exact EKR theorem (for all n) using the shift method. An application of the general theorem gives a similar result for t-intersecting chains if n is large enough.

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عنوان ژورنال:
  • Combinatorica

دوره 20  شماره 

صفحات  -

تاریخ انتشار 2000