exact ⟨ofDerivation b, isProper_ofDerivation b, mem_ofDerivation b⟩
case intro
μ : Type ?u.1106645
L : Language
inst✝⁶ : (k : ℕ) → DecidableEq (L.Func k)
inst✝⁵ : (k : ℕ) → DecidableEq (L.Rel k)
inst✝⁴ : (k : ℕ) → Primcodable (L.Func k)
inst✝³ : (k : ℕ) → Primcodable (L.Rel k)
inst✝² : UniformlyPrimcodable L.Func
inst✝¹ : UniformlyPrimcodable L.Rel
inst✝ : Primcodable μ
Γ : Sequent L
h : Nonempty ( ⊢¹ Γ)
b : { d // CutFree d }
⊢ ∃ l, l.isProper = true ∧ Γ ∈ l.sequents
no goals