\(QS27_{8}^{(2)}\)

Description

Topological configuration of singularities: \(s,a;N,(0,2)SN\)

Phase Portrait

Topological Invariants

TCSP	Fin Sep	Inf Sep
\(27\)	\(41\)	\(2210\)

Example

The quadratic differential system

\[\begin{cases} \dot{x} = -\frac{1}{10}00 + x^{2} + (9 \, x \, y)/5 + (554 \, y^{2})/625 \\ \dot{y} = -\frac{1}{10}00 + x^{2} + y - (1179 \, x \, y)/625 + (2858 \, y^{2})/625 \end{cases}\]

has the following phase portrait done with P4. If you want, you may download the P4 file here.

The phase portrait appears in the following papers

With name \(BD09\) in {J. C. Artés}, Systems of class BD, {Preprint} (2026).