## Abstract We prove that every graph of circumference __k__ has tree‐width at most __k__ − 1 and that this bound is best possible. © 2003 Wiley Periodicals, Inc. J Graph Theory 43: 24–25, 2003
Multiplicities of Eigenvalues and Tree-Width of Graphs
✍ Scribed by Yves Colin de Verdière
- Publisher
- Elsevier Science
- Year
- 1998
- Tongue
- English
- Weight
- 567 KB
- Volume
- 74
- Category
- Article
- ISSN
- 0095-8956
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✦ Synopsis
Using multiplicities of eigenvalues of elliptic self-adjoint differential operators on graphs and transversality, we construct some new invariants of graphs which are related to tree-width.
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