The countable Erds-Menger conjecture with ends

نویسنده

  • Reinhard Diestel
چکیده

Erd˝ os conjectured that, given an infinite graph G and vertex sets A, B ⊆ V (G), there exist a set P of disjoint A–B paths in G and an A–B separator X 'on' P, in the sense that X consists of a choice of one vertex from each path in P. We prove, for countable graphs G, the extension of this conjecture in which A, B and X are allowed to contain ends as well as vertices, and where the closure of A avoids B and vice versa. (Without the closure condition the extended conjecture is false.)

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

دوره 87  شماره 

صفحات  -

تاریخ انتشار 2003