Welcome! You are encouraged to register with the site and login (for free). When you register, you support the site and your question history is saved.
Review: Terms in a Closed-Form Sequence
Explanation
The twelfth term of this sequence will have 
,
so it will be
.
Similarly, the 11th term will be 
.
Therefore, the difference between the two terms will be
If necessary, you can begin calculating to convince
yourself that (D) is way too small. Or you may know that 
(or 1K, in computing terms, e.g., as in a file
that takes up 1K of memory). Note that it was not necessary to compute previous
terms to get the terms we wanted - the terms we wanted could be computed
directly. In math terms, that means that this expression is a closed-form
sequence, not a recursive sequence; GMAT questions may have one or the other.
The correct answer is (E).
If you believe you have found an error in this question or explanation, please contact us and include the question title or URL in your message.