English
If r is an equivalence and r' is contained in r, then a ReflTransGen step implies r a b.
Русский
Если r — эквивалентность и r' ⊆ r, то ReflTransGen r' от a к b implies r a b.
LaTeX
$$$$(\\\\forall a b, r' a b \\\\Rightarrow r a b) \\\\Rightarrow \\\\operatorname{ReflTransGen} r' a b \\\\Rightarrow r a b$$$$
Lean4
theorem reflTransGen_of_equivalence {r' : α → α → Prop} (hr : Equivalence r) :
(∀ a b, r' a b → r a b) → ReflTransGen r' a b → r a b :=
reflTransGen_of_transitive_reflexive hr.1 (fun _ _ _ ↦ hr.trans)