The complexity of nonrepetitive edge coloring of graphs
نویسنده
چکیده
A squarefree word is a sequence w of symbols such that there are no strings x, y, and z for which w = xyyz. A nonrepetitive coloring of a graph is an edge coloring in which the sequence of colors along any open path is squarefree. We show that determining whether a graph G has a nonrepetitive k-coloring is Σ p 2 -complete. When we restrict to paths of lengths at most n, the problem becomes NP-complete for fixed n.
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ورودعنوان ژورنال:
- CoRR
دوره abs/0709.4497 شماره
صفحات -
تاریخ انتشار 2007