Step 1: Divide the number into separate digits:
29043 => 2 9 0 4 3
Step 2: Calculate the distance between each digit and the next (the last digit with the first):
2 to 9 = 7
9 to 0 = 9
0 to 4 = 4
4 to 3 = 1
3 to 2 = 1
Step 3: Combine the filters to a string:
7 9 4 1 1 = 79411