On Restricted Arc-connectivity of Regular Digraphs
نویسندگان
چکیده
The restricted arc-connectivity λ′ of a strongly connected digraph G is the minimum cardinality of an arc cut F in G such that every strongly connected component of G−F contains at least two vertices. This paper shows that for a d-regular strongly connected digraph with order n and diameter k ≥ 4, if λ′ exists, then λ′(G) ≥ min { (n − dk−1)(d− 1) dk−1 + d− 2 , 2d− 2 } As consequences, the restricted arc-connectivity of the de Bruijn and Kautz digraph and the generalized de Bruijn and Kautz digraph are determined.
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