The Lie symmetry group of the general Lienard-type equation

Ágota Figula, Gábor Horváth, Tamás Milkovszki +1

We consider the general Lienard-type equation $\ddot{u}={\sum }_{k=0}^n{f}_k{\dot{u}}^k$ for $n\ge 4$. This equation naturally admits the Lie symmetry $\frac{\partial }{\partial t}$.…