Suppose: 5223 plays:

you take the difference of the first 2 numbers which is: 5-2= 3 and the difference of the last 2 numbers which is: 2-3= 1 this time without symbols...So it will be: 3-1 i call it the Difference Number...The Difference Number is: 3-1....

You then write first 2 numbers you look for all the numbers that have difference of: 3 and they are: (you treat 0 as 10):

0-7

9-6

8-5

7-4

6-3

5-2

4-1

they are 7 pairs...You then do the same with numbers... [ More ]]]>