Cases

Conditions

Bounds

5th case sparse matrix

$\left|a_0\right|+\cdots +\left|a_3\right|<1$

$\left|\lambda \right|\le 1$

Cauchy

${\Vert .\Vert }_{\infty }$

$\left|\lambda \right|\le 1.04$

Montel

${\Vert .\Vert }_1$

$\left|\lambda \right|\le 1$

Carmichel-Mason

${\Vert .\Vert }_2$

$\left|\lambda \right|\le 1.0027462291$

Ovals of Cassini

$\gamma$ , $\delta$

$\left|\lambda \right|\le 1.04$

Dehmer

$M_1$ , ${\varphi }_2$

$\left|\lambda \right|\le 1.05$