English
In a distributive lattice, liminf with respect to a supremum equals the dual of limsup with respect to an infimum: liminf u (f ⊔ g) = limsup u (fᵒᵈ ⊓ gᵒᵈ) etc.
Русский
В распределимой решётке лиминф по верхнему пределу равен двойственности лимиапсо и инфимума: liminf u (f ⊔ g) = liminf u f ⊓ liminf u g, и т.д.
LaTeX
$$$\\operatorname{liminf} u (f \\sqcup g) = \\operatorname{liminf} u f \\sqcap \\operatorname{liminf} u g$$$
Lean4
theorem liminf_sup_filter {g} : liminf u (f ⊔ g) = liminf u f ⊓ liminf u g :=
limsup_sup_filter (α := αᵒᵈ)