Characterizing $(\mathcal{F},\mathcal{G})$-syndetic, $(\mathcal{F},\mathcal{G})$-thick, and related notions of size using derived sets along ultrafilters

Shea D. Burns, Dennis Davenport, Shakuan Frankson +3

We characterize relative notions of syndetic and thick sets using, what we call, "derived" sets along ultrafilters. Manipulations of derived sets is a characteristic feature of alg…