∀ {R : Type u} {N : Type v} [inst : CommSemiring R] {σ : Type u_1} {S : Type u_3} [inst_1 : CommSemiring S]
  [inst_2 : Algebra R S] [inst_3 : CommSemiring N] [inst_4 : Algebra R N] [inst_5 : DecidableEq σ],
  MvPolynomial.rTensorAlgEquiv = AlgEquiv.ofLinearEquiv MvPolynomial.rTensor ⋯ ⋯