intro (_ : step n₁ ≤ step n₂)
ℕ : Type
inst✝³ : Core ℕ
inst✝² : Induction ℕ
inst✝¹ : Addition ℕ
inst✝ : Sign ℕ
order_inst : Order ℕ
n₁ n₂ : ℕ
⊢ step n₁ ≤ step n₂ → n₁ ≤ n₂
ℕ : Type
inst✝³ : Core ℕ
inst✝² : Induction ℕ
inst✝¹ : Addition ℕ
inst✝ : Sign ℕ
order_inst : Order ℕ
n₁ n₂ : ℕ
x✝ : step n₁ ≤ step n₂
⊢ n₁ ≤ n₂