∫ Утверждение Mathlib
preperfect_iff_subset_derivedSet
Mathlib.Topology.DerivedSet
URI: https://scilib.ai/kg/mathlib#preperfect_iff_subset_derivedSet
∫ Утверждение Mathlib
Mathlib.Topology.DerivedSet
URI: https://scilib.ai/kg/mathlib#preperfect_iff_subset_derivedSet