X:
\left(
\begin{array}{ccccc}
0 & 1 & 2 & 3 & 4\\
\frac{1}{2^4} & \frac{4}{2^4} & \frac{6}{2^4} & \frac{4}{2^4} & \frac{1}{2^4}
\end{array}
\right).