exact imp_trans! (implyRightAnd! (generalConj'! (by simp)) (imp_trans! (by simp) ih)) collect_multibox_and!
case hcons
F : Type u_1
inst✝⁷ : StandardModalLogicalConnective F
inst✝⁶ : DecidableEq F
S : Type u_2
inst✝⁵ : System F S
p✝ q r : F
Γ✝ Δ : List F
𝓢 : S
inst✝⁴ : Classical 𝓢
inst✝³ : System.NegationEquiv 𝓢
inst✝² : Necessitation 𝓢
inst✝¹ inst✝ : HasAxiomK 𝓢
n : ℕ
p : F
Γ : List F
h : ¬Γ = []
ih : 𝓢 ⊢! (□'^[n]Γ).conj' ⟶ □^[n]Γ.conj'
⊢ 𝓢 ⊢! (□'^[n](p :: Γ)).conj' ⟶ □^[n](p ⋏ Γ.conj')
no goals