Full list of non-zero Kazhdan-Lusztig-Vogan polynomials:

 0:  0: 1

 1:  1: 1

 2:  0: 1
     2: 1

 3:  1: 1
     3: 1

 4:  2: 1
     4: 1

 5:  3: 1
     5: 1

 6:  4: 1
     6: 1

 7:  5: 1
     7: 1

 8:  6: 1
     8: 1

 9:  7: 1
     9: 1

10:  8: 1
    10: 1

11:  9: 1
    11: 1

12: 10: 1
    11: 1
    12: 1

25 nonzero polynomials, and 30 zero polynomials,
 at 55 Bruhat-comparable pairs.