∀ (a a_1 : ℤ) (a_2 : a % 2 = 1) (b b_1 : ℤ) (b_2 : b % 2 = 1),
  (Dyadic.ofOdd a a_1 a_2).ble (Dyadic.ofOdd b b_1 b_2) =
    match b_1 - a_1 with
    | Int.ofNat l => decide (a <<< l ≤ b)
    | Int.negSucc l => decide (a ≤ b <<< (l + 1))