Characteristic polynomial
$$\begin{equation}\left(\lambda + 1\right)^{2} \left(\lambda + 3\right) \left(\lambda + 5\right)^{2} \left(\lambda - 3\right)^{2} \left(\lambda^{3} + \lambda^{2} - 18 \lambda - 43\right) \left(\lambda^{3} + 13 \lambda^{2} + 74 \lambda + 141\right) \left(\lambda^{3} - 3 \lambda^{2} - 78 \lambda - 163\right)\notag\end{equation}$$
Minimal polynomial
$$\begin{equation}\left(\lambda + 1\right) \left(\lambda + 3\right) \left(\lambda + 5\right) \left(\lambda - 3\right) \left(\lambda^{3} + \lambda^{2} - 18 \lambda - 43\right) \left(\lambda^{3} + 13 \lambda^{2} + 74 \lambda + 141\right) \left(\lambda^{3} - 3 \lambda^{2} - 78 \lambda - 163\right)\notag\end{equation}$$
Quantum multiplication matrix
$$\begin{equation}\begin{pmatrix}0 & 2 & 2 & 8 & 4 & 3 & 9 & 6 & 9 & 12 & 0 & 8 & 8 & 0 & 8 & 0 \\ 1 & -1 & 0 & 1 & 0 & 2 & 6 & 4 & 2 & 4 & 0 & 6 & 6 & 0 & 6 & 0 \\ 1 & 0 & -1 & 1 & 0 & 2 & 2 & 0 & 6 & 4 & 0 & 6 & 6 & 0 & 6 & 0 \\ 1 & 1 & 1 & -1 & 2 & 0 & 0 & 0 & 0 & 0 & -4 & 0 & 0 & 0 & 0 & 0 \\ 1 & 0 & 0 & 1 & -2 & 0 & 2 & 2 & 2 & 8 & 8 & 3 & 9 & 6 & 9 & 8 \\ 0 & 1 & 1 & 0 & 0 & -2 & 1 & 0 & 1 & 0 & 0 & 4 & 4 & 0 & 4 & 0 \\ 0 & 1 & -1 & 2 & -1 & 1 & -1 & 2 & 0 & 1 & 0 & -2 & -2 & -4 & -6 & -6 \\ 0 & 1 & 1 & -1 & 2 & 0 & 0 & -3 & 0 & 0 & 0 & 4 & 8 & 8 & 8 & 12 \\ 0 & 0 & 2 & 1 & 1 & 1 & 0 & 0 & -1 & 1 & 0 & 2 & 2 & 0 & 6 & 6 \\ 0 & 0 & 0 & 2 & 1 & 0 & 1 & 1 & 1 & -1 & 2 & 0 & 0 & 0 & 0 & 0 \\ 0 & 0 & 0 & 0 & 1 & 0 & 0 & 0 & 0 & 1 & -2 & 0 & 2 & 2 & 2 & 3 \\ 0 & 0 & 0 & 0 & 0 & 2 & 1 & 1 & 1 & -2 & -1 & -2 & 0 & -1 & 0 & 4 \\ 0 & 0 & 0 & 0 & 0 & 0 & 2 & 1 & 0 & 2 & -1 & 1 & -1 & 2 & 0 & -2 \\ 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 0 & 1 & 3 & 0 & 1 & -2 & 1 & 4 \\ 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 2 & 3 & 2 & 1 & 1 & 1 & 0 & 2 \\ 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 2 & 3 & 2 & 3 & 0\end{pmatrix}\notag\end{equation}$$