Step 1: Divide the number into separate digits:
2026 => 2 0 2 6
Step 2: Calculate the distance between each digit and the next (the last digit with the first):
2 to 0 = 2
0 to 2 = 2
2 to 6 = 4
6 to 2 = 4
Step 3: Combine the filters to a string:
2 2 4 4 = 2244