English
For every ordinal o, lift(preAleph(o)) = preAleph(lift(o)).
Русский
Пусть o — ординал. Тогда lifting(preAleph(o)) = preAleph(lift(o)).
LaTeX
$$$$ \forall o:\mathrm{Ordinal}, \operatorname{lift}(\operatorname{preAleph}(o)) = \operatorname{preAleph}(\operatorname{lift}(o)). $$$$
Lean4
@[simp]
theorem lift_preAleph (o : Ordinal.{u}) : lift.{v} (preAleph o) = preAleph (Ordinal.lift.{v} o) :=
(preAleph.toInitialSeg.trans liftInitialSeg).eq (Ordinal.liftInitialSeg.trans preAleph.toInitialSeg) o