On the Number of Birch Partitions

نویسنده

  • Stephan Hell
چکیده

Birch and Tverberg partitions are closely related concepts from discrete geometry. We show two properties for the number of Birch partitions: Evenness, and a lower bound. This implies the first non-trivial lower bound for the number of Tverberg partitions that holds for arbitrary q, where q is the number of partition blocks. The proofs are based on direct arguments, and do not use the equivariant method from topological combinatorics. We furthermore investigate whether these results admit a topological version.

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عنوان ژورنال:
  • Discrete & Computational Geometry

دوره 40  شماره 

صفحات  -

تاریخ انتشار 2008