$\"\"$

Consider the few generations of your family starting with yur parents.

Diagram of the situation:

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Observe the pattern in tha diagram.

Each generation forms a geometric sequence $\"\"$ .

Find the total number of ancestors by calculating sum of geometric sequence $\"\"$ .

The geometric sequence with $\"\"$ , $\"\"$ and $\"\"$ .

Sum of the geometric sequence is $\"\"$ .

$\"\"$

$\"\"$ .

Total number of ancestors for $\"\"$ generations is $\"\"$ .

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Total number of ancestors for $\"\"$ generations is $\"\"$ .