The bandwidth of the Hamming graph (the product, (Kn) d , of complete graphs) has been an open question for many years. Recently Berger-Wolf and Rheingold [1] pointed out that the bandwidth of a numbering of the Hamming graph may be interpreted as a measure of the e ects of noise in the multi-channe
Interval degree and bandwidth of a graph
β Scribed by Fedor V Fomin; Petr A Golovach
- Publisher
- Elsevier Science
- Year
- 2003
- Tongue
- English
- Weight
- 395 KB
- Volume
- 129
- Category
- Article
- ISSN
- 0166-218X
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β¦ Synopsis
The interval degree id(G) of a graph G is deΓΏned to be the smallest max-degree of any interval supergraphs of G. One of the reasons for our interest in this parameter is that the bandwidth of a graph is always between id(G)=2 and id(G). We prove also that for any graph G the interval degree of G is at least the pathwidth of G 2 . We show that if G is an AT-free claw-free graph, then the interval degree of G is equal to the clique number of G 2 minus one. Finally, we show that there is a polynomial time algorithm for computing the interval degree of AT-free claw-free graphs.
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