English
If a function is measurable with respect to the σ-algebra generated by the first coordinates, then it depends only on those coordinates up to i.
Русский
Если функция measurability относится к σ-алгебре, порожденной первыми координатами, то она зависит только от этих координат до i.
LaTeX
$$$$ \text{DependsOn } f (Iic\ i). $$$$
Lean4
/-- If a function is measurable with respect to the σ-algebra generated by the
first coordinates, then it only depends on those first coordinates. -/
theorem _root_.Measurable.dependsOn_of_piLE [MeasurableSpace Z] [MeasurableSingletonClass Z]
(hf : Measurable[piLE i] f) : DependsOn f (Iic i) :=
dependsOn_iff_factorsThrough.2 hf.factorsThrough