1−2[−2101]\frac{1}{-2}\left[\begin{array}{cc}-2 & 1 \\0 & 1\end{array}\right]−21[−2011]
1−3[−2101]\frac{1}{-3}\left[\begin{array}{cc}-2 & 1 \\0 & 1\end{array}\right]−31[−2011]
1−2[1−10−2]\frac{1}{-2}\left[\begin{array}{ll}1 & -1 \\0 & -2\end{array}\right]−21[10−1−2]
1−3[1−10−2]\frac{1}{-3}\left[\begin{array}{ll}1 & -1 \\0 & -2\end{array}\right]−31[10−1−2]
