A characterization of a real hypersurface of type B

Moreover, Takagi [13] proved that if a real hypersurface of PnC has two or three distinctconstant principal curvatures, then M is locally congruent to the case of the homogeneous ones of type Ax, A2 or B. In what follows the induced almost contact metric structure of the real hypersurface of Mn{c) is denoted by (0, g, |, rj). The structure vector £is said to be principal if A£=a£, where A is the shape operator in the direction of the unit normal C and a = v)(Ag). Real hypersurfaces of PnC have been studied by many differentialgeometers ([2], [4], [51, [6] and [7] etc.) and as one of them. Kimura [5] asserts