## Abstract A vertex set __X__ of a digraph __D__ = (__V, A__) is a __kernel__ if __X__ is independent (i.e., all pairs of distinct vertices of __X__ are non‐adjacent) and for every __v__ ∈ __V__‐__X__ there exists __x__ ∈ __X__ such that __vx__ ∈ __A__. A vertex set __X__ of a digraph __D__ = (__V
On the existence of (k, l)-kernels in digraphs
✍ Scribed by Hortensia Galeana-Sánchez
- Publisher
- Elsevier Science
- Year
- 1990
- Tongue
- English
- Weight
- 264 KB
- Volume
- 85
- Category
- Article
- ISSN
- 0012-365X
No coin nor oath required. For personal study only.
✦ Synopsis
In this paper we present some results on the existence of /c-kernels and (k, [)-kernels in digraphs which generalize the following Theorem of P. Duchet [2]: "If every directed cycle of odd length in a digraph D has at least two symmetrical arcs, then D has a kernel.
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