English
In any partial order, the weak cover relation is the reflexive-generated closure of the cover relation.
Русский
В произвольном частичном порядке слабое покрытие равно рефлексивному замыканию покрытия.
LaTeX
$$$ \mathrm{WCovBy}(x,y) \iff \mathrm{ReflGen}(\mathrm{CovBy})(x,y) $$$
Lean4
theorem wcovBy_eq_reflGen_covBy [PartialOrder α] : (· ⩿ · : α → α → Prop) = ReflGen (· ⋖ ·) := by ext x y;
simp_rw [wcovBy_iff_eq_or_covBy, @eq_comm _ x, reflGen_iff]