On the cardinality of lower sets and universal discretization

F. Dai, A. Prymak, A. Shadrin +2

A set $Q$ in ${\mathbb{Z}}_{+}^d$ is a lower set if $(k_1,\dots ,k_d)\in Q$ implies $(l_1,\dots ,l_d)\in Q$ whenever $0\le l_i\le k_i$ for all $i$. We derive new and refine known results…