English
The open-interval diamond isomorphism is established by a pair of monotone maps between Ioo intervals in a modular lattice.
Русский
Установлено diamond-изоморфизм между открытыми интервалами через пары монотонных отображений.
LaTeX
$$$\text{InfIooOrderIsoIooSup}(a,b): Ioo(a\wedge b,a) \simeq_o Ioo(b,a\vee b).$$$
Lean4
instance complementedLattice_Icc [Fact (a ≤ b)] : ComplementedLattice (Set.Icc a b) where
exists_isCompl := fun ⟨x, ha, hb⟩ => by
simp_rw [Set.Icc.isCompl_iff]
obtain ⟨y, rfl, rfl⟩ := exists_inf_eq_and_sup_eq ha hb
exact ⟨⟨y, inf_le_right, le_sup_right⟩, rfl, rfl⟩