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Highly connected non-2-linked digraphs. (English) Zbl 0746.05030
A digraph $$D$$ is said to be 2-linked if for any four vertices $$x_ 1$$, $$x_ 2$$, $$y_ 1$$, and $$y_ 2$$ there exist disjoint directed paths $$P_ 1$$ and $$P_ 2$$ starting at $$x_ 1$$ and $$x_ 2$$ and ending at $$y_ 1$$ and $$y_ 2$$, respectively. The author shows that for every positive integers $$k$$ there exists a strongly $$k$$-connected digraph $$D$$ that is not 2-linked.

##### MSC:
 05C20 Directed graphs (digraphs), tournaments 05C38 Paths and cycles 05C40 Connectivity
##### Keywords:
directed graphs; paths
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##### References:
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