∀ {R : Type u_1} {ι : Type u_2} {M₁ : ι → Type u_3} {M₂ : Type u_4} [inst : Semiring R]
  [inst_1 : (i : ι) → AddCommMonoid (M₁ i)] [inst_2 : AddCommGroup M₂] [inst_3 : (i : ι) → Module R (M₁ i)]
  [inst_4 : Module R M₂] (n : ℕ) (a : MultilinearMap R M₁ M₂),
  SubNegMonoid.zsmul (Int.negSucc n) a = -SubNegMonoid.zsmul (↑n.succ) a