English
The equality pi'_pi holds for encodable index with SigmaFinite μ i, giving the same product formula as pi'_pi.
Русский
Уравнение pi'_pi выполняется для кодируемого индекса и сигма-ограниченных μ_i, причем формула совпадает с произведением.
LaTeX
$$pi' μ evaluated on universal product equals ∏ i μ_i(s_i)$$
Lean4
/-- The product measure on an encodable finite type, defined by mapping `Measure.tprod` along the
equivalence `MeasurableEquiv.piMeasurableEquivTProd`.
The definition `MeasureTheory.Measure.pi` should be used instead of this one. -/
def pi' : Measure (∀ i, α i) :=
Measure.map (TProd.elim' mem_sortedUniv) (Measure.tprod (sortedUniv ι) μ)