, Volume 35, Issue 1, pp 171–192 | Cite as

Tree Sets

  • Reinhard Diestel


We study an abstract notion of tree structure which lies at the common core of various tree-like discrete structures commonly used in combinatorics: trees in graphs, order trees, nested subsets of a set, tree-decompositions of graphs and matroids etc.

Unlike graph-theoretical or order trees, these tree sets can provide a suitable formalization of tree structure also for infinite graphs, matroids, and set partitions. Order trees reappear as oriented tree sets.

We show how each of the above structures defines a tree set, and which additional information, if any, is needed to reconstruct it from this tree set.


Tree Order Nested Graph Matroid Protree 


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Copyright information

© The Author(s) 2017

Authors and Affiliations

  1. 1.Hamburg UniversityHamburgGermany

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