12 stages, 4 taps:  (9 sets)

[12, 11, 10, 4]
[12, 11, 10, 2]
[12, 11, 8, 6]
[12, 11, 7, 4]
[12, 10, 9, 3]
[12, 10, 5, 4]
[12, 9, 8, 5]
[12, 9, 7, 6]
[12, 8, 6, 5]


12 stages, 6 taps:  (43 sets)

[12, 11, 10, 9, 8, 4]
[12, 11, 10, 9, 6, 4]
[12, 11, 10, 9, 6, 2]
[12, 11, 10, 9, 4, 3]
[12, 11, 10, 9, 4, 2]
[12, 11, 10, 8, 7, 3]
[12, 11, 10, 8, 7, 2]
[12, 11, 10, 8, 6, 4]
[12, 11, 10, 8, 6, 1]
[12, 11, 10, 8, 5, 1]
[12, 11, 10, 8, 2, 1]
[12, 11, 10, 7, 6, 3]
[12, 11, 10, 7, 6, 2]
[12, 11, 10, 7, 5, 2]
[12, 11, 10, 7, 2, 1]
[12, 11, 10, 6, 3, 2]
[12, 11, 9, 8, 7, 6]
[12, 11, 9, 8, 7, 4]
[12, 11, 9, 8, 4, 1]
[12, 11, 9, 8, 3, 1]
[12, 11, 9, 7, 6, 5]
[12, 11, 9, 7, 6, 4]
[12, 11, 9, 7, 3, 1]
[12, 11, 9, 6, 5, 3]
[12, 11, 9, 5, 4, 1]
[12, 11, 8, 7, 6, 3]
[12, 11, 8, 7, 5, 4]
[12, 11, 8, 6, 5, 2]
[12, 11, 8, 5, 4, 2]
[12, 11, 7, 5, 4, 3]
[12, 11, 6, 4, 3, 2]
[12, 10, 9, 8, 7, 6]
[12, 10, 9, 8, 7, 3]
[12, 10, 9, 8, 6, 2]
[12, 10, 9, 8, 4, 3]
[12, 10, 9, 8, 4, 2]
[12, 10, 9, 7, 5, 2]
[12, 10, 9, 6, 4, 3]
[12, 10, 9, 6, 4, 2]
[12, 10, 8, 7, 6, 2]
[12, 9, 8, 7, 5, 3]
[12, 9, 8, 7, 4, 3]
[12, 9, 8, 6, 5, 4]


12 stages, 8 taps:  (18 sets)

[12, 11, 10, 9, 8, 7, 6, 3]
[12, 11, 10, 9, 8, 7, 4, 3]
[12, 11, 10, 9, 8, 6, 5, 4]
[12, 11, 10, 9, 8, 5, 2, 1]
[12, 11, 10, 9, 8, 4, 3, 1]
[12, 11, 10, 9, 7, 6, 5, 1]
[12, 11, 10, 9, 7, 3, 2, 1]
[12, 11, 10, 9, 6, 5, 4, 1]
[12, 11, 10, 9, 6, 5, 2, 1]
[12, 11, 10, 8, 6, 5, 4, 2]
[12, 11, 10, 8, 6, 4, 3, 1]
[12, 11, 10, 7, 6, 5, 4, 1]
[12, 11, 10, 7, 5, 4, 3, 1]
[12, 11, 9, 8, 7, 6, 4, 1]
[12, 11, 9, 7, 6, 5, 4, 2]
[12, 11, 8, 7, 5, 4, 3, 2]
[12, 10, 9, 8, 7, 5, 3, 2]
[12, 10, 9, 8, 6, 5, 4, 2]


12 stages, 10 taps:  (2 sets)

[12, 11, 10, 9, 8, 7, 5, 4, 3, 2]
[12, 11, 10, 9, 8, 7, 5, 4, 3, 1]