Planar Turan number of intersecting triangles

被引：13

作者：

Fang, Longfei ^{[1
]}

Wang, Bing ^{[1
]}

Zhai, Mingqing ^{[1
]}

机构：

[1] Chuzhou Univ, Sch Math & Finance, Chuzhou 239012, Anhui, Peoples R China

来源：

DISCRETE MATHEMATICS | 2022年 / 345卷 / 05期

基金：

中国国家自然科学基金;

关键词：

Turan number; Planar graph; Friendship graph; EXTREMAL GRAPHS;

D O I：

10.1016/j.disc.2021.112794

中图分类号：

O1 [数学];

学科分类号：

0701 ; 070101 ;

摘要：

The planar Turan number of a given graph H, denoted by ex(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 vertex. In this paper, we obtain sharp bounds of ex(P)(n, H-k) and ex(P)(n, K-1 + Pk+1) for all non-trivial cases, which improve the corresponding results of Lan, Shi and Song in ((2019) [9]). (c) 2022 Elsevier B.V. All rights reserved.

引用

页数：10

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