Date: Friday, September 30, 2022
Time: 2:45 – 3:45 PM (coffee starting at 2:30 PM)
Room: Herzberg room 4351 (MacPhail Room)
Title: List version of the 1-2-3 conjecture
Speaker: Prof. Xuding Zhu, Zhejiang Normal University

Abstract:  The well-known 1-2-3 Conjecture by Karonski, Luczak and Thomason states that the edges of any connected graph with at least three vertices can be assigned weights 1, 2 or 3 so that for each edge uv the sums of the weights at u and at v are distinct.

The list version of the 1-2-3 Conjecture by Bartnicki, Grytczuk and Niwczyk states that the same holds if each edge e has the choice of weights not necessarily from {1,2,3}, but from any set {x(e),y(e),z(e)} of three real numbers.

The goal of this talk is to survey developments on the 1-2-3 Conjecture, especially on the list version of the 1-2-3 Conjecture.

Short Bio:  Prof. Zhu received his Ph.D from University of Calgary in 1990.

Before joining Zhejiang Normal University as a chair professor, he worked at National Sun Yat-sen University in Taiwan.

In 2007, he received the Academic Prize from the Taiwan Mathematical Society. He has published over 200 papers in the broad area of discrete mathematics and his work on graph coloring is highly influential. He also serves on the editorial boards of several journals such as Journal of Graph Theory, Discrete Mathematics, SIAM Journal on Discrete Math, European Journal of Combinatorics.

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