Deltahedra pyramidal

Box 4 gives an overview over some simple polyhedra with their number of comers, faces and edges that will be taken into account in the following. Except for the deltahedra [R3], [R4], [R5], and [R ] that are defined by equilateral triangles only, two awft-polyhedra with the number of comers and faces inter-changed are included. One of these has only square faces (cube), the other, the trigonal prism, like the also included square pyramid has mixed faces, i.e., triangles and squares. 

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