Discrete symmetries of nonlinear ordinary differential equations

A method proposed by P. E. Hydon for determining discrete symmetries of ordinary differential equations once the Lie symmetry algebra is known is considered. It is also used to determine the real discrete point symmetries of some equations. We give also a brief overview of continuous symmetry transformations as well as a discussion about symmetries in general. Finally, a new type of discrete and nonlocal symmetry introduced by N. Euler, T. Wolf, P.G.L Leach and M. Euler connected to the generalized Sundman transformation is investigated, namely the Sundman symmetry.Validerat; 20101217 (root