16. There are 2011 street lamps numbered $1,2, \cdots, 2011$ on the road. To save electricity, it is required to turn off 300 of these lamps, but no two adjacent lamps can be turned off at the same time, and the lamps at both ends cannot be turned off. The number of ways to satisfy these conditions is $\qquad$ (express the result using combination notation).
16. $C_{1710}^{300}$.

The problem is equivalent to inserting 300 dark lamps into 1711 paths. Therefore, there are $\mathrm{C}_{1710}^{300}$ ways to turn off the lamps.