cluster     1   number of spheres in cluster     4
    1  -6.05400   0.55300  17.18600   0.700    1                                
    2  -5.25500   1.47400  17.53000   0.700    2                                
    3  -5.67500  -0.68200  17.48700   0.700    3                                
    4  -7.09400   0.68800  16.54100   0.700    4