A modular $k\!$-coloring, $k\ge 2,$ of a graph $G$ is a coloring of the vertices of $G$ with the elements in $\mathbb{Z}_k$ having the property that for every two adjacent vertices of $G,$ the sums of the colors of their neighbors are different in $\mathbb{Z}_k.$ The minimum $k$ for which $G$ has a modular $k\!$-coloring is the modular chromatic number of $G.$ Except for some special cases, modular chromatic number of $C_m\square P_n$ is determined.
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Paramaguru, N. and Sampathkumar, R. (2013). Modular chromatic number of $C_m \square P_n$. Transactions on Combinatorics, 2(2), 47-72. doi: 10.22108/toc.2013.2943
MLA
Paramaguru, N. , and Sampathkumar, R. . "Modular chromatic number of $C_m \square P_n$", Transactions on Combinatorics, 2, 2, 2013, 47-72. doi: 10.22108/toc.2013.2943
HARVARD
Paramaguru, N., Sampathkumar, R. (2013). 'Modular chromatic number of $C_m \square P_n$', Transactions on Combinatorics, 2(2), pp. 47-72. doi: 10.22108/toc.2013.2943
CHICAGO
N. Paramaguru and R. Sampathkumar, "Modular chromatic number of $C_m \square P_n$," Transactions on Combinatorics, 2 2 (2013): 47-72, doi: 10.22108/toc.2013.2943
VANCOUVER
Paramaguru, N., Sampathkumar, R. Modular chromatic number of $C_m \square P_n$. Transactions on Combinatorics, 2013; 2(2): 47-72. doi: 10.22108/toc.2013.2943