Multiply 2 by 1/2 to get 1.
Multiply 1 by 2/3 to get 2/3.
Multiply 2/3 by 3/4 to get 6/12 = 1/2.
Multiply 1/2 by 4/5 to get 4/10 = 2/5.
Multiply 2/5 by 5/6 to get 10/30 = 1/3.
Multiply 1/3 by 6/7 to get 6/21 = 2/7. (I suspect there's a typo in the question.)
And so on, so that the <em>n</em>th term in the sequence is multiplied by <em>n</em>/(<em>n</em> + 1) to get the (<em>n</em> + 1)th term.
Recursively, the sequence is given by
We can solve this exactly by iterating:
and so on down to
or
and with lots of cancellation, we end up with
