**Assignment 12**

**Excel Spreadsheet Exercise**

**by Debra Jackson**

In this exercise we are asked to place four numbers in the first row as follows

A B C D

For each successive row replace the entries by the absolute value of the difference of the entry just above and the entry just to the right in the previous row. In the fourth position use the absolute value of the difference of the fourth and the first (i.e. cycle)

|A-B| |B-C| |C-D| |D-A|

Will the process lead to a 0 in all 4 entries for some row and what is the largest number of rows before a zero row is generated?

Yes, the process will lead to a 0 in all 4 entries for some row. The question is how many rows are calculated before a row of with all 0's is formed. I tried quite a few combinations of numbers and finally found the following which calculated all 0's in the 10th row.

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