2 01 0 Every planar graph without adjacent short cycles is 3 - colorable
نویسنده
چکیده
Two cycles are adjacent if they have an edge in common. Suppose that G is a planar graph, for any two adjacent cycles C1 and C2, we have |C1| + |C2| ≥ 11, in particular, when |C1| = 5, |C2| ≥ 7. We show that the graph G is 3-colorable.
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