THE RIGIDITY OF CLIFFORD TORUS S-1(ROOT-1 N)XS(N-1)(ROOT-N-1/N)/

In this paper, we prove that if M is an n-dimensional closed minimal h ypersurface with two distinct principal curvatures of a unit sphere S- n+1(1), then S = n and M is a Clifford torus if n less than or equal t o S less than or equal to n + [2n(2)(n + 4)/3(n(n + 4) + 4)], where S is the squared norm of the second fundamental form of M.