symm
case right
n : ℕ
i : Fin n
this :
  ArithPart₁ fun v =>
    rfind fun x => Part.some (decide ((fun x x => x * x) v x ≤ v.get i ∧ v.get i < (fun x x => x * x) v (x + 1)))
v : Vector ℕ n
m : ℕ
hm : m < (v.get i).sqrt
⊢ false = (decide (m * m ≤ v.get i) && decide (v.get i < (m + 1) * (m + 1)))
case right
n : ℕ
i : Fin n
this :
  ArithPart₁ fun v =>
    rfind fun x => Part.some (decide ((fun x x => x * x) v x ≤ v.get i ∧ v.get i < (fun x x => x * x) v (x + 1)))
v : Vector ℕ n
m : ℕ
hm : m < (v.get i).sqrt
⊢ (decide (m * m ≤ v.get i) && decide (v.get i < (m + 1) * (m + 1))) = false