14 research outputs found
Line-graphs of cubic graphs are normal
A graph is called normal if its vertex set can be covered by cliques and also
by stable sets, such that every such clique and stable set have non-empty
intersection. This notion is due to Korner, who introduced the class of normal
graphs as an extension of the class of perfect graphs. Normality has also
relevance in information theory. Here we prove, that the line graphs of cubic
graphs are normal.Comment: 16 pages, 10 figure