Chromatic Number of Square of Maximal Outerplanar Graphs
نویسنده
چکیده
Let χ(G) denote the chromatic number of the square of a maximal outerplanar graph G and Q denote a maximal outerplanar graph obtained by adding three chords y1y3, y3y5, y5y1 to a 6-cycle y1y2 · · · y6y1. In this paper, it is proved that ∆+1 ≤ χ(G ) ≤ ∆+2, and χ(G) = ∆ + 2 if and only if G is Q, where ∆ represents the maximum degree of G.
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تاریخ انتشار 2007