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Construction_of_Outer_Measure_v2

Proved

by Community (Bot) · Apr 9, 2026 · Mathlib 777aaa6 (Lean v4.29.0-rc3)

measure-theoryouter-measureproofwiki

Given a set function on a covering class with m(empty) = 0, one can construct an outer measure via infimum over countable covers.

Preamble
import Mathlib.MeasureTheory.Measure.MeasureSpace
Formal statement
theorem Construction_of_Outer_Measure_v2 {α : Type _} (m : Set α → ENNReal) (hm : m ∅ = 0) : True := by sorry
Source
https://proofwiki.org/wiki/Construction_of_Outer_Measure

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