On kernel-perfect critical digraphs
نویسندگان
چکیده
In this paper we investigate new sufficient conditions for a digraph to be kernel-perfect (KP) and some structural properties of kernel-perfect critical (KPC) digraphs. In particular, it is proved that the asymmetrical part of any KPC digraph is strongly connected. A new method to construct KPC digraphs is developed. The existence of KP and KPC digraphs with arbitrarily large dichromatic number is also discussed.
منابع مشابه
Some results on the structure of kernel-perfect and critical kernel-imperfect digraphs
A kernel N of a digraph D is an independent set of vertices of D such that for every w ∈ V (D) − N there exists an arc from w to N . The digraph D is said to be a kernel-perfect digraph when every induced subdigraph of D has a kernel. Minimal non kernel-perfect digraphs are called critical kernel imperfect digraphs. In this paper some new structural results concerning finite critical kernel imp...
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ورودعنوان ژورنال:
- Discrete Mathematics
دوره 59 شماره
صفحات -
تاریخ انتشار 1986