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Example 2: Adding Up and Down

When you add counting numbers in a sequence (like 1 + 2 + 1 or 1 + 2 + 3 + 2 + 1), you can see that
the result is also a square number. For example:

 1 = 1

 1 + 2 + 1 = 4

 1 + 2 + 3 + 2 + 1 = 9

This pattern continues, and the sequence of numbers added up and then down forms square
numbers like 4, 9, 16, 25, and so on.

Both examples show different ways of visualising and understanding how sequences of numbers can
create square numbers.