论文标题
平面Turán的相交三角形的数量
Planar Turán Number of intersecting triangles
论文作者
论文摘要
给定图$ H $的平面Turán数量，由$ ex _ {\ Mathcal {p}}}（n，h）$表示，是$ n $顶点上所有平面图上不包含$ h $的副本的所有平面图的最大边数。让$ h_k $成为友谊图，它是通过共享一个共同的顶点从$ k $三角形获得的。在本文中，我们获得了$ ex _ {\ mathcal {p}}}（n，h_k）$和$ ex _ {\ Mathcal {p}}}（n，k_1+p_1+p_ {k+1} $ $ k \ ge2 $的急剧界限。 J. Combin。 26（2）（2019），\＃P2.11。
The planar Turán number of a given graph $H$, denoted by $ex_{\mathcal{P}}(n,H)$, is the maximum number of edges over all planar graphs on $n$ vertices that do not contain a copy of $H$ as a subgraph. Let $H_k$ be a friendship graph, which is obtained from $k$ triangles by sharing a common vertex. In this paper, we obtain sharp bounds of $ex_{\mathcal{P}}(n,H_k)$ and $ex_{\mathcal{P}}(n,K_1+P_{k+1})$ for $k\ge2$, which improves the results of Lan and Shi in Electron. J. Combin. 26 (2) (2019), \#P2.11.
