These charts were made fairly manually, and haven't yet been checked through an automated method. (For now, verify errors on your own or use at your own risk.)
 Understanding Centermost counting

This documentation is based on lefttoright reading (like words found in standard English, and unlike words found in Hebrew or Arabic, but perhaps like numbers even in Hebrew and Arabic).
This is based on information from RFC 3531 section 3.3 or information derived from the logic of that RFC section.
Standard binary counting places the order of columns in MSB order (with the “most significant” bits on the left), so the values of each column are in this order:
128 64 32 16 8 4 2 1
RFC 1219 reverses it, placing the order of columns in LSB order (“least significant” bits on the left), so the values of each column are in this order:
1 2 4 8 32 16 32 64 128
RFC 3531's Centermost strategy orders columns in this order:
128 32 8 2 1 4 16 64
That is, it starts in the middle (offset a bit to the right if there is an even number of digits). The next column to be added is the column to the left of what is already used. The next column to be added is the column to the right of what is already used. (After that, once again, the next column to be added is the column to the left of what is already used. Then, the next column to be added is the column to the right of what is already used.) The pattern continues, flipflopping between adding to the left and adding to the right.
So, after 0 (00000000 binary), which is a subnet that should probably be skipped, the next number is 8 (00001000 binary), and then 16 (00010000 binary), and then 24 (00011000 binary), and then 4 (00000100 binary), and then 12 (00001100 binary), and then 20 (00010100 binary), and then 28 (00011100 binary), 


(Some numbers below here are currently just provided in binary form.





That is the first 8 charts.
The next 8 charts are like the first eight charts, but with one added (so they are all odd numbers).
The 8 charts after that are like the first eight charts, but with 128 added (so all the numbers will be even).
The 8 charts after that are like the first eight charts, but with 129 added (so, once again, they will all be odd numbers).