Perhaps it is much easier to do it in mapdl where we can use *DO (for loops) to create nodes (N commands) as needed, and elements (E commands). See the help manual for more info on logic and looping, and the N command on how to define nodes and E for elements.
When the mesh is done, then we can issue the CDWRITE command in mapdl. This will write the .cdb file that can be read into external model in WB.
All the best