On separable and H-separable polynomials in skew polynomial rings of several variables

Let B be a ring with 1, and {rho(1), ..., rho(e)} a set of automorphisms of B. Let B[x(1), ..., X-e; rho(1), ..., rho(e); {u(ij)} be the skew polynomial ring of automorphism type. In this paper, we shall give equivalent conditions that the residue ring of B[X-1, ..., X-e; rho(1,) ..., rho(e);{u(ij)}] by the ideal generated by a set {X-1(m1) - u(1), ..., X-e(me) - u(e)}to be separable or H-separable over B.