  A method of representation of a solution as segments of the series in powers
of the step of the independent variable is expanded for solving complex systems
of ordinary differential equations (ODE): the Lorenz system and other systems.
A new procedure of reduction of the representation of the solution to a sum of
two parts (regular and random) is performed. A shifting procedure is applied in
each level of the independent variable to the random part and it acts as the
filter that extracts the values to the regular part. In certain cases it is
possible to omit the random part and construct the approximation which does not
converge but still provides the qualitative information about the full solution
(a linear approximation provides a simple exact solution). Evaluation of the
error for this case is performed. Constructing the analytical representation of
the solutions for these systems by the developed method is presented.
