$\"\"$

The sigma notation of the sequence is $\"\"$ .

$\"\"$

$\"\"$ .

The first term of the sequence is $\"\"$ and last term $\"\"$ .

The number of terms is equal to the upper bound minus the lower bound plus one $\"\"$ .

The sum of the series is $\"\"$ .

Substitute $\"\"$ and last term $\"\"$ and $\"\"$ .

$\"\"$

$\"\"$ .

The sum of the series $\"\"$ . $\"\"$

$\"\"$ .