Cases
Conditions
Bounds
5th case of sparse matrix
| a 0 | + ⋯ + | a 3 | < 1
| λ | ≤ 1
Cauchy
‖ . ‖ ∞
| λ | ≤ 1.00001
Montel
‖ . ‖ 1
Carmichel-Mason
‖ . ‖ 2
| λ | ≤ 1.0000000000505
Ovals of Cassini
γ , δ
Dehmer
M 1 , ϕ 2
| λ | ≤ 1.000001