741*. Which years of the $XX$ century can be represented in the form $2^{n}-2^{k}$, where $n$ and $k$ are natural numbers? Find all such years.
$\triangle$ Let the desired year be denoted as $\overline{19 x y}$. Then

$$
\overline{19 x y}=2^{n}-2^{k}, \quad 2^{n}=\overline{19 x y}+2^{k}
$$

Therefore, $2^{n}>\overline{19 x y}$, from which it follows that $n>10$.

Consider several cases.

1) Suppose $n=11$. We get:

$$
\overline{19 x y}=2048-2^{k}
$$

The values $k=1,2,3,4,5$ are too small. The values $k=6$ and $k=7$ work:

$$
2048-2^{6}=2048-64=1984, \quad 2048-2^{1}=2048-128=1920 .
$$

But the value $k=8$ is too large:

$$
2048-2^{8}=2048-256=1792\overline{19 x y}
$$

And the value $k=12$ is already too large.

3) Similarly, it can be shown that there are no solutions for $n=13$. And so on.

Answer: $1984,1920$.