2019/11/6 李渭天教授專題演講
演講者：李渭天 教授
國立中興大學應用數學系
日 期：2019年11月6日（星期三）14:30
地 點：國立高雄大學理學院408室
講 題：Shifted-antimagic Labelings for Graphs
摘 要：
The concept of antimagic labelings of a graph is to produce distinct vertex sums by labeling edges through consecutive numbers starting from one. A long-standing conjecture is that every connected graph, except a single edge, is antimagic. Some graphs are known to be antimagic, but little has been known about sparse graphs, not even trees.
In this talk, we will study a weak version called k-shifted-antimagic labelings which allow the consecutive numbers starting from k + 1, instead of starting from 1, where k can be any integer. We establish connections among various concepts proposed in the literature of antimagic labelings and extends previous results in three aspects:
- Some classes of graphs, including trees and graphs whose vertices are of odd degrees, which have not been veri_ed to be antimagic are shown to be k-shifted-antimagic for su_ciently large k.
- Some graphs are proved k-shifted-antimagic for all k, while some are proved not for some particular k.
- Disconnected graphs are also considered.
Joint work with Fei-Huang Chang, Hong-Bin Chen, and Zhishi Pan.