An edge coloring of a graph G with colors 1,2,...,t is called an interval t-coloring if for each i ∈ {1,2,...,t} there is at least one edge of G colored by i, and the colors of edges incident to any vertex of G are distinct and form an interval of integers. A graph G is interval colorable, if there is an integer t ≥ 1 for which G has an interval t-coloring. Let ℜ be the set of all interval colorable graphs. In 2004 Kubale and Giaro showed that if G,H ∈ 𝔑, then the Cartesian product of these graphs belongs to 𝔑. Also, they formulated a similar problem for the lexicographic product as an open problem. In this paper we first show that if G ∈ 𝔑, then G[nK₁] ∈ 𝔑 for any n ∈ ℕ. Furthermore, we show that if G,H ∈ 𝔑 and H is a regular graph, then strong and lexicographic products of graphs G,H belong to 𝔑. We also prove that tensor and strong tensor products of graphs G,H belong to 𝔑 if G ∈ 𝔑 and H is a regular graph.
@article{bwmeta1.element.bwnjournal-article-doi-10_7151_dmgt_1551, author = {Petros A. Petrosyan}, title = {Interval edge colorings of some products of graphs}, journal = {Discussiones Mathematicae Graph Theory}, volume = {31}, year = {2011}, pages = {357-373}, zbl = {1234.05103}, language = {en}, url = {http://dml.mathdoc.fr/item/bwmeta1.element.bwnjournal-article-doi-10_7151_dmgt_1551} }
Petros A. Petrosyan. Interval edge colorings of some products of graphs. Discussiones Mathematicae Graph Theory, Tome 31 (2011) pp. 357-373. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-doi-10_7151_dmgt_1551/
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