\(QS28_{3}^{(2)}\)

Description

Topological configuration of singularities: \(s,s,sn;N,N,N\)

Phase Portrait

Phase Portrait Graphic Design

Topological Invariants

TCSP	Fin Sep	Inf Sep
\(28\)	\(443\)	\(311211\)

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 \(U^2_AD,17\) in {J. C. Artés}, Structurally unstable quadratic vector fields of codimension two: families possessing one finite saddle-node and a separatrix connection, Qual. Theory Dyn. Syst. { bf 23} (2024), no.~1, Paper No. 40, 88 pp.; MR4662466