∀ {R : Type u} {M : Type v} [inst : CommMonoid R] [inst_1 : AddMonoid M] [inst_2 : DistribMulAction R M]
  [inst_3 : DistribMulAction Rᵐᵒᵖ M] [IsCentralScalar R M] (x : TrivSqZeroExt R M) (n : ℕ),
  (x ^ n).snd = n • x.fst ^ n.pred • x.snd