English
For any family f i j of lower sets, the complement distributes over the double infimum: (⨅ i ⨅ j, f i j).compl = ⨅ i ⨅ j, (f i j).compl.
Русский
Для двойного произведения нижних множеств справедлив комплемент: (⨅ i ⨅ j, f(i,j)).compl = ⨅ i ⨅ j, f(i,j).compl.
LaTeX
$$$ (\bigsqcap_{i,j} f(i,j)).\mathrm{compl} = \bigsqcap_{i,j} (f(i,j)).\mathrm{compl} $$$
Lean4
@[simp]
theorem compl_iInf₂ (f : ∀ i, κ i → LowerSet α) : (⨅ (i) (j), f i j).compl = ⨅ (i) (j), (f i j).compl := by
simp_rw [LowerSet.compl_iInf]