xn 3  pxn 8  palbits 3 ppalbits 8
  M #      0 = 1000 0001   :   2
    Members:
    ...
    abc

sigmas with   2 members: 1
  M #      1 = 1100 0011   :   4
    Members:
    ...
    a..
    .bc
    abc

  M #      2 = 1010 0101   :   4
    Members:
    ...
    .b.
    a.c
    abc

  M #      3 = 1001 1001   :   4
    Members:
    ...
    ab.
    ..c
    abc

sigmas with   4 members: 3
  M #      4 = 1111 1111   :   8
    Members:
    ...
    a..
    .b.
    ab.
    ..c
    a.c
    .bc
    abc

sigmas with   8 members: 1

n = 3, sigma count 5.