MarceloSales

A subset $A\subseteq \mathbb Z$ of integers is free if for every two distinct subsets $B, B'\subseteq A$ we have \Pisier asked if for every subset $A\subseteq \mathbb Z$ of integers the following two statement are equivalent: (i) $A$ is a union of finitely many free sets. (ii) There exists $\epsilon>0$ such that every finite …