Maximal Density of Integral Sets with Missing Differences and the Kappa Values
Maximal Density of Integral Sets with Missing Differences and the Kappa Values
Let $M$ be a given set of positive integers. A set $S$ of nonnegative integers is said to be an $M$-set if $a,b \in S$ implies $a-b \notin M$. In an unpublished problem collection, Motzkin asked to find maximal upper asymptotic density, denoted by $\mu(M)$, of $M$-sets. The first published …