The hypercube ( offset ) family is the first of three regular polytope families , labeled by Coxeter as Î n. The other two are the hypercube dual family , the cross-polytopes , labeled as Î n , and the simplices , labeled as Î n. A fourth family , the infinite tessellation of hypercubes , he labeled as Î n. The hypercube ( offset ) family is one of three regular polytope families , labeled by Coxeter as Î n. The other two are the hypercube dual family , the cross-polytopes , labeled as Î n , and the simplices , labeled as Î n. A fourth family , the infinite tessellations of hypercubes , he labeled as Î n.