Kernels and some operations in edge-coloured digraphs
نویسندگان
چکیده
Let D be an edge-coloured digraph, V (D) will denote the set of vertices of D; a set N ⊆ V (D) is said to be a kernel by monochromatic paths of D if it satisfies the following two conditions: For every pair of different vertices u, v ∈ N there is no monochromatic directed path between them and; for every vertex x ∈ V (D) − N there is a vertex y ∈ N such that there is an xy -monochromatic directed path. In this paper we consider some operations on edge-coloured digraphs, and some sufficient conditions for the existence or uniqueness of kernels by monochromatic paths of edge-coloured digraphs formed by these operations from another edge-coloured digraphs.
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عنوان ژورنال:
- Discrete Mathematics
دوره 308 شماره
صفحات -
تاریخ انتشار 2008