have := self_dvd_abs x
case neg.refine'_1
a x : ℤ
hodd : Odd x
h0' : x ≠ 0
c : ℤ := a % x
hc : c = a % x
H : natAbs x ≤ 2 * natAbs (a % x)
⊢ c - abs x + (a + abs x) / x * x = a
case neg.refine'_1
a x : ℤ
hodd : Odd x
h0' : x ≠ 0
c : ℤ := a % x
hc : c = a % x
H : natAbs x ≤ 2 * natAbs (a % x)
this : x ∣ abs x
⊢ c - abs x + (a + abs x) / x * x = a