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## 'Differs' printed from http://nrich.maths.org/

Choose any 4 whole numbers, for example (100, 2, 37, 59). Now
take the difference between consecutive numbers, always subtracting
the smaller from the larger, and ending with the difference between
the first and the last numbers. What happens when you repeat this
process over and over again? For example, continue the sequence of
4-tuples:

(100, 2, 37, 59), (98, 35, 22, 41), (63, 13, 19, 57),
(50, 6, 38, 6) , ...

Investigate starting with different sets of 4 numbers.

What happens when you use 3 numbers, or 5, or 6, or 7 or 8
numbers?