Other Structures
It has been shown that the following are not in general reconstructible:
- Digraphs: Infinite families of non-reconstructible digraphs are known, including tournaments (Stockmeyer) and non-tournaments (Stockmeyer). A tournament is reconstructible if it is not strongly connected. A weaker version of the reconstruction conjecture has been conjectured for digraphs, see New digraph reconstruction conjecture.
- Hypergraphs (Kocay).
- Infinite graphs. Let T be a tree on an infinite number of vertices such that every vertex has infinite degree. The counterexample is T and 2T. The question of reconstructibility for locally finite infinite graphs is still open.
Read more about this topic: Reconstruction Conjecture
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—Friedrich Nietzsche (1844–1900)
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