LexBFS-Orderings and Power of Graphs
نویسندگان
چکیده
1 I n t r o d u c t i o n Powers of graphs play an impor t an t role for solving cer tain problems re la ted to dis tances in graphs : p -cen te r and q-dispers ion (el. [7, 3]), k d o m i n a t i o n and k -s tab i l i ty (of. [8, 3]), d iamete r (of. [13]), k -colour ing (cf. [26, 20]) and approx ima t ion of bandwid th (el. [27]). For instance, consider the k-co lour ing problem. The vertices of a g raph have to be coloured by a minimal number of colours such t h a t no two vertices a t dis tance a t mos t k have the same eolour. Obviously, k-colour ing a graph is equivalent to colour (in the classical sense) * First author supported by DAAD, second author supported by DFG.
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