M = \left[
\begin{array}{lll}
 1 & 1 & 1 \\
 1 & 0 & 1 \\
 1 & 1 & 1
\end{array}
\right] \Rightarrow M^2 = \left[
\begin{array}{lll}
 3 & 2 & 3 \\
 2 & 2 & 2 \\
 3 & 2 & 3
\end{array}
\right]