The Colin de Verdi
نویسنده
چکیده
In 1990, Y. Colin de Verdi ere introduced a new graph parameter (G), based on spectral properties of matrices associated with G. He showed that (G) is monotone under taking minors and that planarity of G is characterized by the inequality (G) 3. Recently Lovv asz and Schrijver showed that linkless embeddability of G is characterized by the inequality (G) 4. In this paper we give an overview of results on (G) and of techniques to handle it.
منابع مشابه
On the behaviour of Colin
For any connected undirected graph G, let (G) be the graph invariant introduced by Colin de Verdi ere. In this paper we study the behaviour of (G) under clique sums of graphs. In particular, we give a forbidden minor characterization of those clique sums G of G 1 and G 2 for which (G) = maxf(G 1); (G 2)g.
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تاریخ انتشار 1997