You can put this solution on YOUR website! That is a geometric series,
the sum of the first 17 terms of the form ,
because .
That sum is and , so
NOTE:
Your teacher/instructor may insist on seeing formulas, such as , or .
Humoring teachers and bosses may be essential to survival,
but I do not believe math is about memorizing.
Remembering ideas that led others to a way to calculate results is OK.
That way we do not have to rediscover gunpowder every time,
but I refuse to memorize.