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What is the smallest number of dicycles in a dicycle decomposition of an eulerian digraph?

✍ Scribed by Nathaniel Dean


Publisher
John Wiley and Sons
Year
1986
Tongue
English
Weight
408 KB
Volume
10
Category
Article
ISSN
0364-9024

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✦ Synopsis


A digraph D with n vertices is said to be decomposable into a set S of dicycles if every arc of D is contained in exactly one member of S. Counterexamples are given to the following conjectures which are generalizations of three well-known conjectures by G. Hajos, P. Erdos, and P. J. Kelly: (1) [B. Jackson] Every eulerian-oriented graph is decomposable into at most $ dicycles. (2) [W. Bienia & H. Meyniel] Every eulerian digraph is decomposable into at most n dicycles.

Certain observations lead us to make three other conjectures: (a) Every eulerian-oriented graph is decomposable into a t most ? dicycles. (b) Every symmetric digraph with n > 1 is decomposable into at most 2n -3 dicycles. (c) Every eulerian digraph with n > 1 is decomposable into at most $ -3 dicycles.