Abstract:
A k-tuple coloring of a graph G assigns a set of k colors to each vertex of G such that if two vertices are adjacent, the corresponding sets of colors are disjoint. The k-tuple chromatic number of G, χk(G), is the smallest t so that there is a k-tuple coloring of G using t colors. It is well known that χ(G□H)=max{χ(G),χ(H)}. In this paper, we show that there exist graphs G and H such that χk(G□H)>max{χk(G),χk(H)} for k≥2. Moreover, we also show that there exist graph families such that, for any k≥1, the k-tuple chromatic number of their Cartesian product is equal to the maximum k-tuple chromatic number of its factors. © 2017 Elsevier B.V.
Registro:
Documento: |
Artículo
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Título: | k-tuple colorings of the Cartesian product of graphs |
Autor: | Bonomo, F.; Koch, I.; Torres, P.; Valencia-Pabon, M. |
Filiación: | CONICET and DC, FCEN, Universidad de Buenos Aires, Argentina Instituto de Industria, Universidad Nacional de General Sarmiento, Argentina Universidad Nacional de Rosario and CONICET, Argentina Université Paris-13, Sorbonne Paris Cité LIPN, CNRS UMR7030, Villetaneuse, France
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Palabras clave: | Cartesian product of graphs; Cayley graphs; Hom-idempotent graphs; k-tuple colorings; Kneser graphs; Color; Graphic methods; Set theory; Cartesian product of graphs; Cartesian Products; Cayley graphs; Chromatic number; Graph G; Idempotent; Kneser graph; Graph theory |
Año: | 2017
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Volumen: | 245
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Página de inicio: | 177
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Página de fin: | 182
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DOI: |
http://dx.doi.org/10.1016/j.dam.2017.02.003 |
Título revista: | Discrete Applied Mathematics
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Título revista abreviado: | Discrete Appl Math
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ISSN: | 0166218X
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CODEN: | DAMAD
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Registro: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_0166218X_v245_n_p177_Bonomo |
Referencias:
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Citas:
---------- APA ----------
Bonomo, F., Koch, I., Torres, P. & Valencia-Pabon, M.
(2017)
. k-tuple colorings of the Cartesian product of graphs. Discrete Applied Mathematics, 245, 177-182.
http://dx.doi.org/10.1016/j.dam.2017.02.003---------- CHICAGO ----------
Bonomo, F., Koch, I., Torres, P., Valencia-Pabon, M.
"k-tuple colorings of the Cartesian product of graphs"
. Discrete Applied Mathematics 245
(2017) : 177-182.
http://dx.doi.org/10.1016/j.dam.2017.02.003---------- MLA ----------
Bonomo, F., Koch, I., Torres, P., Valencia-Pabon, M.
"k-tuple colorings of the Cartesian product of graphs"
. Discrete Applied Mathematics, vol. 245, 2017, pp. 177-182.
http://dx.doi.org/10.1016/j.dam.2017.02.003---------- VANCOUVER ----------
Bonomo, F., Koch, I., Torres, P., Valencia-Pabon, M. k-tuple colorings of the Cartesian product of graphs. Discrete Appl Math. 2017;245:177-182.
http://dx.doi.org/10.1016/j.dam.2017.02.003