Generalized Verma modules over sln+2 induced from U(hn)-free sln+1-modules

A class of generalized Verma modules over sln+2 are constructed from sln+1-modules which are U(hn)-free modules of rank 1. The necessary and sufficient conditions for these sln+2-modules to be simple are determined. This leads to a class of new simple sln+2-modules.