Normalizer of the nonsplit Cartan case

This is one of the six possible cases for the {{ KNOWL('ec.q.galois_rep_image', 'image of the mod $p$ Galois Representation')}} if $p$ is a {{ KNOWL('ec.q.non-surjective_prime', 'non-surjective prime')}} for $E$. The label **Nn** means that $G$ is contained in the normalizer of the nonsplit Cartan subgroup but not in the nonsplit Cartan subgroup itself. The label **Nn.a.b** denotes the subgroup of the normalizer of the nonsplit Cartan subgroup generated by \[ \begin{pmatrix}a&rb\\b&a\end{pmatrix}, \begin{pmatrix}1&0\\0&-1\end{pmatrix}. \] where $r$ be the least positive integer that generates $\F_p^*$.