exact final_solution_nat g
case intro
g : ℕ → ℕ
⊢ ((∀ (m n : ℕ), g (n + g m) ≤ g n + m) ∧ (∀ (m n : ℕ), m ≤ g n + g (n + g m)) ∧ ∀ (m n : ℕ), g n ≤ g (n + g m) + m) ↔
    (fun a => g a) = fun a => a
no goals