The Extremal Function for Two Disjoint Cycles∗
نویسندگان
چکیده
A theta graph is the union of three internally disjoint paths that have the same two distinct end vertices. We show that every graph of order n ≥ 9 and size at least b7n−13 2 c contains two disjoint theta graphs. We also show that every 2-edge-connected graph of order n ≥ 6 and size at least 3n− 5 contains two disjoint cycles, such that any specified vertex with degree at least three belongs to one of them. The lower bound on size in both are sharp in general.
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تاریخ انتشار 2013