Step 1: Divide the number into separate digits:
00556 => 0 0 5 5 6
Step 2: Calculate the distance between each digit and the next (the last digit with the first):
0 to 0 = 0
0 to 5 = 5
5 to 5 = 0
5 to 6 = 1
6 to 0 = 6
Step 3: Combine the filters to a string:
0 5 0 1 6 = 05016