English
If r is transitive, then TransGen r equals r as a binary relation.
Русский
Если r транзитивно, то TransGen r равняется r как бинарное отношение.
LaTeX
$$$ \forall {α} {r : α \to α \to \mathrm{Prop}}, \mathrm{Transitive} r \to \mathrm{TransGen} r = r $$$
Lean4
theorem transGen_eq_self (trans : Transitive r) : TransGen r = r :=
funext fun a ↦
funext fun b ↦
propext <|
⟨fun h ↦ by
induction h with
| single hc => exact hc
| tail _ hcd hac => exact trans hac hcd,
TransGen.single⟩