Quasi-kernels and quasi-sinks in infinite graphs
نویسندگان
چکیده
Given a directed graph G = (V, E) an independent set A ⊂ V is called quasi-kernel (quasi-sink) iff for each point v there is a path of length at most 2 from some point of A to v (from v to some point of A). Every finite directed graph has a quasikernel. The plain generalization for infinite graphs fails, even for tournaments. We investigate the following conjecture here: for any digraph G = (V, E) there is a a partition (V0, V1) of the vertex set such that the induced subgraph G[V0] has a quasi-kernel and the induced subgraph G[V1] has a quasi-sink.
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ورودعنوان ژورنال:
- Discrete Mathematics
دوره 309 شماره
صفحات -
تاریخ انتشار 2009