(X : 𝒫 (𝒫 (𝒫 A))) : ((𝒫 (𝒫 (𝒫 A))) : Type@{A}). Proof. revert X. nrapply power_morph. nrapply power_morph. nrapply power_inj. Defined.
From HoTT Require Import TruncType ExcludedMiddle Modalities.ReflectiveSubuniverse abstract_algebra HSet. From HoTT Require Import Universes.Smallness. From HoTT Require Import Spaces.Card. From HoTT.Sets Require Import Ordinals Powers.