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Theorems · Definition · measure theory

IsPiSystem

{α : Type u_1} → Set (Set α) → Prop

A π-system is a collection of subsets of α that is closed under binary intersection of non-disjoint sets. Usually it is also required that the collection is nonempty, but we don't do that here.

Defined in
Mathlib.MeasureTheory.PiSystem
Cited by
88 results in Mathlib
Foundations
Depth 6 from the axioms · uses no axioms

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Cites2

Mathlib declarations this one mentions in its statement or cites explicitly in its proof. Plumbing is filtered out.

  • Setstatement and proof · cited by 53,352
  • Set.Nonemptyproof · cited by 2,627

Cited by88

Results whose statement or proof uses this declaration.