Intermediate rings between D+I And K y1,#x2026;,yt

摘要

Let R = k [y1,…,yt] be an affine domain (where k is a field) having krull dimension =n0. Let I be a nonzero proper ideal of R and D be a subring of K. In section 1 we determine necessary and sufficient conditions in order that (S,R) is a 'lying over pair' where S = D+I. In section 2 we chaaracterize when S is a Maximal non-Noetherian subring of R. Further we determine when S is a maximal subring of R.