For all positive integers n less than 2002, let
a_n \equal{} \begin{cases} 11 & \text{if }n\text{ is divisible by }13\text{ and }14 \\
13 & \text{if }n\text{ is divisible by }11\text{ and }14 \\
14 & \text{if }n\text{ is divisible by }11\text{ and }13 \\
0 & \text{otherwise} \end{cases}
Calculate \sum_{n \equal{} 1}^{2001} a_n.
<spanclass=′latex−bold′>(A)</span>448<spanclass=′latex−bold′>(B)</span>486<spanclass=′latex−bold′>(C)</span>1560<spanclass=′latex−bold′>(D)</span>2001<spanclass=′latex−bold′>(E)</span>2002