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arXiv · 1106.3453

On the Locating Chromatic Number of the Cartesian Product of Graphs

Ali Behtoei·Behnaz Omoomi
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Abstract

Let $c$ be a proper $k$-coloring of a connected graph $G$ and $Π=(C_1,C_2,...,C_k)$ be an ordered partition of $V(G)$ into the resulting color classes. For a vertex $v$ of $G$, the color code of $v$ with respect to $Π$ is defined to be the ordered $k$-tuple $c_{{}_Π}(v):=(d(v,C_1),d(v,C_2),...,d(v,C_k)),$ where $d(v,C_i)=\min\{d(v,x) | x\in C_i\}, 1\leq i\leq k$. If distinct vertices have distinct color codes, then $c$ is called a locating coloring. The minimum number of colors needed in a locating coloring of $G$ is the locating chromatic number of $G$, denoted by $\Cchi_{{}_L}(G)$. In this paper, we study the locating chromatic number of grids, the cartesian product of paths and complete graphs, and the cartesian product of two complete graphs.

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Ali Behtoei, Behnaz Omoomi. 2012-12-09. On the Locating Chromatic Number of the Cartesian Product of Graphs. https://arxiv.org/abs/1106.3453

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