new F ∧ H → (A ∧ D → (((A → B) → G) → ((D ∨ C → E) → ((C → D) → (D → (H → E ∨ (E ∨ H)))))))
intro
cases 0
intro
cases 3
intro
intro
intro
cases 0
cases 3
intro
cases 0
cases 3
intro
cases 0
cases 3
left
apply 7
left
exact 5