Let P(n) be the class of all connected graphs having exactly n ~> 1 negative eigenvalues (including their multiplicities). In this paper we prove that the class P(n) contains only finitely many so-called canonical graphs. The analogous statement for the class Q(n) of all connected graphs having exac
Graphs with a Small Number of Nonnegative Eigenvalues
✍ Scribed by Miroslav Petrović
- Publisher
- Springer Japan
- Year
- 1999
- Tongue
- English
- Weight
- 130 KB
- Volume
- 15
- Category
- Article
- ISSN
- 0911-0119
No coin nor oath required. For personal study only.
📜 SIMILAR VOLUMES
If D is an acyclic digraph, its competition graph is an undirected graph with the same vertex set and an edge between vertices x and y if there is a vertex a so that (x, a) and (y, a) are both arcs of D. If G is any graph, G together with sufficiently many isolated vertices is a competition graph, a
In this paper, all connected bipartite graphs are characterized whose third largest Laplacian eigenvalue is less than three. Moreover, the result is used to characterize all connected bipartite graphs with exactly two Laplacian eigenvalues not less than three, and all connected line graphs of bipart
Let G be a graph on n vertices. We show that if the total number of isomorphism types of induced subgraphs of G is at most &II', where E < lo-\*', then either G or its complement contain an independent set on at least (1 -4e)n vertices. This settles a problem of Erdiis and Hajnal.