\(QS99_{2}^{(4)}\)

Description

Topological configuration of singularities: \(sn,a;(1,1)SN,S,N\)

Phase Portrait

Phase Portrait Graphic Design

Topological Invariants

TCSP	Fin Sep	Inf Sep
\(99\)	\(30\)	\(111110\)

Example

The quadratic differential system

\[\begin{cases} \dot{x} = P_x(x,y) \\ \dot{y} = P_y(x,y) \end{cases}\]

has the following phase portrait done with P4.

The phase portrait appears in the following papers

With name \(7.7L1\) in {J. C. Artés, M. C. Mota and A. C. Rezende}, Quadratic differential systems with a finite saddle-node and an infinite saddle-node $(1, 1)SN$ - $({ rm B)$}, Internat. J. Bifur. Chaos Appl. Sci. Engrg. { bf 31} (2021), no.~9, Paper No. 2130026, 110 pp.; MR4291723

Missed in:

{X. Huang}, Qualitative analysis or certain nonlinear differential equations, {Ph.D. U. Delft}, (1996).