Degree versions of the Erdős-Ko-Rado theorem and Erdős hypergraph matching conjecture

نویسندگان

  • Hao Huang
  • Yi Zhao
چکیده

We use an algebraic method to prove a degree version of the celebrated Erdős-Ko-Rado theorem: given n > 2k, every intersecting k-uniform hypergraph H on n vertices contains a vertex that lies on at most ( n−2 k−2 ) edges. This result implies the Erdős-Ko-Rado Theorem as a corollary. It can also be viewed as a special case of the degree version of a well-known conjecture of Erdős on hypergraph matchings. Improving the work of Bollobás, Daykin, and Erdős from 1976, we show that, given integers n, k, s with n ≥ 3ks, every k-uniform hypergraph H on n vertices with minimum vertex degree greater than ( n−1 k−1 ) − ( n−s k−1 ) contains s disjoint edges.

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عنوان ژورنال:
  • J. Comb. Theory, Ser. A

دوره 150  شماره 

صفحات  -

تاریخ انتشار 2017