English
If f maps α to β with finite α and a measurableSingletonClass, then essInf f .count equals the iInf of f(a).
Русский
Если α конечен и есть класс единичных подмножеств, essInf f .count равен iInf f(a).
LaTeX
$$$[Finite α] (hf : BddBelow (Set.range f)) : \operatorname{essInf} f (MeasureTheory.uniformOn univ) = \iInf a, f a$.$$
Lean4
/-- Essential supremum of `f` with respect to measure `μ`: the smallest `c : β` such that
`f x ≤ c` a.e. -/
def essSup {_ : MeasurableSpace α} (f : α → β) (μ : Measure α) :=
(ae μ).limsup f