Detour Chromatic Numbers
نویسندگان
چکیده
The nth detour chromatic number, χn(G) of a graph G is the minimum number of colours required to colour the vertices of G such that no path with more than n vertices is monocoloured. The number of vertices in a longest path of G is denoted by τ (G) . We conjecture that χn(G) ≤ d τ(G) n e for every graph G and every n ≥ 1 and we prove results that support the conjecture. We also present some sufficient conditions for a graph to have nth chromatic number at most 2.
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ورودعنوان ژورنال:
- Discussiones Mathematicae Graph Theory
دوره 21 شماره
صفحات -
تاریخ انتشار 2001