rw [shadow, shadow]
case intro.intro
α : Type u_1
inst✝ : LinearOrder α
s U V : Finset α
n r k i : ℕ
𝒜 𝒞 : Finset (Finset (Fin n))
h₁ : Set.Sized r ↑𝒜
h₂ : 𝒞.card ≤ 𝒜.card
h₃ : IsInitSeg 𝒞 r
𝒜' : Finset (Finset (Fin n))
prop : 𝒜' ⊆ 𝒜
size : 𝒜'.card = 𝒞.card
⊢ ∂ 𝒜' ⊆ ∂ 𝒜
case intro.intro
α : Type u_1
inst✝ : LinearOrder α
s U V : Finset α
n r k i : ℕ
𝒜 𝒞 : Finset (Finset (Fin n))
h₁ : Set.Sized r ↑𝒜
h₂ : 𝒞.card ≤ 𝒜.card
h₃ : IsInitSeg 𝒞 r
𝒜' : Finset (Finset (Fin n))
prop : 𝒜' ⊆ 𝒜
size : 𝒜'.card = 𝒞.card
⊢ (𝒜'.sup fun s => image s.erase s) ⊆ 𝒜.sup fun s => image s.erase s