Birings and plethories of integer-valued polynomials
Let and be commutative rings with identity. An is an -algebra together with a lift of the functor from -algebras to sets to a functor from -algebras to -algebras. An is a monoid object in the monoidal category, equipped with the composition product, of --birings. The polynomial ring is an initial object in the category of such structures. The -algebra has such a structure if is a domain such that the natural -algebra homomorphism is an isomorphism for and injective for...