have : step n < m ∨ step n ≃ m := le_split ‹step n ≤ m›
ℕ : Type
inst✝³ : Core ℕ
inst✝² : Induction ℕ
inst✝¹ : Addition ℕ
inst✝ : Sign ℕ
order_inst : Order ℕ
n✝ m : ℕ
motive : ℕ → Prop := fun n => AA.OneOfThree (n < m) (n ≃ m) (n > m)
n : ℕ
ih : AA.OneOfThree (n < m) (n ≃ m) (n > m)
a✝ : n < m
this : step n ≤ m
⊢ AA.OneOfThree (step n < m) (step n ≃ m) (step n > m)
ℕ : Type
inst✝³ : Core ℕ
inst✝² : Induction ℕ
inst✝¹ : Addition ℕ
inst✝ : Sign ℕ
order_inst : Order ℕ
n✝ m : ℕ
motive : ℕ → Prop := fun n => AA.OneOfThree (n < m) (n ≃ m) (n > m)
n : ℕ
ih : AA.OneOfThree (n < m) (n ≃ m) (n > m)
a✝ : n < m
this✝ : step n ≤ m
this : step n < m ∨ step n ≃ m
⊢ AA.OneOfThree (step n < m) (step n ≃ m) (step n > m)