9 stages, 2 taps:  (1 set)

[9, 5]


9 stages, 4 taps:  (8 sets)

[9, 8, 7, 2]
[9, 8, 6, 5]
[9, 8, 5, 4]
[9, 8, 5, 1]
[9, 8, 4, 2]
[9, 7, 6, 4]
[9, 7, 5, 2]
[9, 6, 5, 3]


9 stages, 6 taps:  (14 sets)

[9, 8, 7, 6, 5, 3]
[9, 8, 7, 6, 5, 1]
[9, 8, 7, 6, 4, 3]
[9, 8, 7, 6, 4, 2]
[9, 8, 7, 6, 3, 2]
[9, 8, 7, 6, 3, 1]
[9, 8, 7, 6, 2, 1]
[9, 8, 7, 5, 4, 3]
[9, 8, 7, 5, 4, 2]
[9, 8, 6, 5, 4, 1]
[9, 8, 6, 5, 3, 2]
[9, 8, 6, 5, 3, 1]
[9, 7, 6, 5, 4, 3]
[9, 7, 6, 5, 4, 2]


9 stages, 8 taps:  (1 sets)

[9, 8, 7, 6, 5, 4, 3, 1]