A Hamming graph is a Cartesian product of complete graphs. We show that (finite or infinite) quasi-median graphs, which are a generalization of median graphs, are exactly the retracts of Hamming graphs. This generalizes a result of Bandelt (1984,
Invariant Hamming graphs in infinite quasi-median graphs
β Scribed by Marc Chastand; Norbert Polat
- Publisher
- Elsevier Science
- Year
- 1996
- Tongue
- English
- Weight
- 593 KB
- Volume
- 160
- Category
- Article
- ISSN
- 0012-365X
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β¦ Synopsis
It is shown that a quasi-median graph G without isometric infinite paths contains a Hamming graph (i.e., a cartesian product of complete graphs) which is invariant under any automorphism of G, and moreover if G has no infinite path, then any contraction of G into itself stabilizes a finite Hamming graph.
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