20F69 20F65 2 20E08 1 20F05 1 20F18 1 22A15 1 54D35 1 Lamplighter groups 1 Stone-\(\check{C}\)ech compactification 1 \(G\)-space 1 condensation groups 1 discrete Heisenberg group 1 geodesic growth 1 groups of intermediate growth 1 relative combinatorial derivation 1 space of marked groups 1 sparse and scattered subsets 1 ultracompanion 1