higherDepthTable -- Creates hashtable of Jan-Erik Roos' examples of quadratic ideals with positive depth

i1 : higherDepthTable

o1 = HashTable{1 => ideal 0                           }
                           2
               2 => ideal x
                            2   2
               3 => ideal (x , y )
                            2
               4 => ideal (x , x*y)
                            2   2   2
               5 => ideal (x , y , z )
                            2   2
               6 => ideal (x , y  + x*z, y*z)
                            2   2
               8 => ideal (x , y , x*z)
                            2        2
               9 => ideal (x , x*y, y )
                             2
               10 => ideal (x , x*y, x*z)
                                       2   2
               23 => ideal (x*z, x*u, y , z )
                                  2
               26 => ideal (x*z, y , y*u, z*u)
                                       2
               27 => ideal (x*y, x*z, y , y*z)
                             2             2   2
               50 => ideal (x , x*y, x*z, y , z )
                             2             2
               52 => ideal (x , x*y, x*z, y , y*z)
                             2             2        2
               68 => ideal (x , x*y, x*z, y , y*z, z )

o1 : HashTable