The structure of 2-separations of infinite matroids

نویسندگان

  • Elad Aigner-Horev
  • Reinhard Diestel
  • Luke Postle
چکیده

Generalizing a well known theorem for finite matroids, we prove that for every (infinite) connected matroid M there is a unique tree T such that the nodes of T correspond to minors of M that are either 3-connected or circuits or cocircuits, and the edges of T correspond to certain nested 2-separations of M . These decompositions are invariant under duality.

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

دوره 116  شماره 

صفحات  -

تاریخ انتشار 2016