Two remarks on retracts of graph products
✍ Scribed by Sandi Klavžar
- Publisher
- Elsevier Science
- Year
- 1992
- Tongue
- English
- Weight
- 545 KB
- Volume
- 109
- Category
- Article
- ISSN
- 0012-365X
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✦ Synopsis
KlavZar, S., Two remarks on retracts of graph products, Discrete Mathematics 109 (1992) 155-160.
Let H be a bipartite graph and let G,, be the Mycielski graph with x(G) = n, n 3 4. Then the chromatic number of the strong product of G, by H is at most 2n -2. We use this result to show that there exist strong products of graphs in which a projection of a retract onto a factor is not a retract of the factor. We also show that in the Cartesian product of graphs G and H, any triangles of G transfer in H, whenever G and H are connected and G is stronglytriangulated, weakly-triangulated or four-cycle free.
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