Abstract:
In the framework of an exactly solvable model with nonrenormalizable interaction (Edwards'
equation) a method of differential interpolation is put forward and investigated; this enables one
to construct series of a modified perturbation theory in powers of $g^{\nu}(\ln g)^{n_\nu}$, where $n_\nu$ is an
integer and $\nu$ in the general case is not an integer. It is shown that the approximate solutions
differ from the exact solutions only by finite terms.