The Prenucleolus (Prescision=14 places): 

x1 = 5.499999999999998 
x2 = 5.499999999999998 
x3 = 6.000000000000006 

Excesses:

3.000000000000000 ( )
-0.000000000000004 ( 1 2 3 )
-5.499999999999998 ( 2 )
-5.499999999999998 ( 1 )
-5.500000000000004 ( 2 3 )
-5.500000000000004 ( 1 3 )
-6.000000000000006 ( 3 )
-10.999999999999996 ( 1 2 )

Vector v:

3.000000000000000 ( )
0.000000000000000 ( 3 )
0.000000000000000 ( 2 )
6.000000000000000 ( 2 3 )
0.000000000000000 ( 1 )
6.000000000000000 ( 1 3 )
0.000000000000000 ( 1 2 )
17.000000000000000 ( 1 2 3 )