报 告 人：史永堂 教授（南开大学）
报告题目：Planar anti-Ramsey numbers and Turan numbers for paths and cycles
报告时间：2017年11月1日（周三）16：00
报告地点：静远楼1506报告厅
报告人简介：
史永堂，南开大学教授，博导。2004年获西北大学理学学士学位，2009年6月获南开大学理学博士学位。2009年起在南开大学组合数学中心工作，2014-2015年加拿大西门菲沙大学访问学者，曾受邀到美国、德国、奥地利等国访问交流。研究领域为图论与组合优化。出版专著1部，发表学术论文50余篇。主持国家自然科学基金面上项目2项。入选天津市人才发展特殊支持计划“青年拔尖人才”、南开大学“百名青年学科带头人培养计划”等。
报告摘要：
Motivated by anti-Ramsey numbers introduced by Erdos, Simonovits and Sos in 1975, we study the anti-Ramsey problem when host graphs are plane triangulations. The planar anti-Ramsey number of H, is the maximum number k such that no edge-coloring of any plane triangulation with k colors contains a rainbow copy of H.
The study of planar anti-Ramsey number (under the name of rainbow numbers) was initiated by Hornak, Jendrol', Schiermeyer and Sotak [J Graph Theory 78 (2015) 248-257].
Turan-type problems was initiated by Mantel (1907) and Turan (1941), which was generalized soon by Erdos et al. Dirac (1964) and Mader (1967) started to investigate extremal problems for H-minor-free graphs. The planar Turan number of H, is the maximum number of edges of any H-free planar graph on n vertices. Dowden [J. Graph Theory 83 (2016) 213-230] began the study of planar Turan numbers (under the name of ``extremal planar graphs).
In this talk, we present some results on planar anti-Ramsey numbers and Turan numbers for paths and cycles. Joint work with Yongxin Lan, Suil O and Zi-Xia Song.