3 papers
math.CO2026
A disproof of the uniform witness conjecture
Zixiang Xu
The study of -uniform set systems with VC-dimension at most links the Erdős--Ko--Rado theorem with VC-dimension. But already in 1997, Ahlswede and Khachatrian showed tha…
math.CO2025
Largest -uniform set systems with VC-dimension
Jian Wang, Zixiang Xu, Shengtong Zhang
We determine the largest size of -uniform set systems on with VC-dimension for all .
math.CO2025
Uniform set systems with small VC-dimension
Ting-Wei Chao, Zixiang Xu, Chi Hoi Yip +1
We investigate the longstanding problem of determining the maximum size of a -uniform set system with VC-dimension at most . Since the seminal 1984 work of Frankl and Pac…