English
If s is finite, there exists a finite t such that for every π ∈ s the infimum of π and splitMany I t equals the filter of splitMany I t by subboxes contained in π.iUnion.
Русский
Если s конечно, существует конечное t такое, что dla каждого π ∈ s тождество минимального π и splitMany I t равно фильтру splitMany I t по подкоробкам, вложенным в π.iUnion.
LaTeX
$$$\\exists t:Finset(\\iota\\times\\mathbb{R}),\\ \\forall \\pi \\in s,\\ \\pi \\inf splitMany\\ I\\ t = (splitMany\\ I\\ t)\\!\\cap\\!\\{J:\\text{Box}\\mid J\\subseteq \\pi.iUnion\\}$$$
Lean4
theorem exists_splitMany_inf_eq_filter_of_finite (s : Set (Prepartition I)) (hs : s.Finite) :
∃ t : Finset (ι × ℝ), ∀ π ∈ s, π ⊓ splitMany I t = (splitMany I t).filter fun J => ↑J ⊆ π.iUnion :=
haveI := fun π (_ : π ∈ s) => eventually_splitMany_inf_eq_filter π
(hs.eventually_all.2 this).exists