The simplicity and the efficiency of a quasi-analytical method for solving nonlinear ordinary differential equations (ODE) is illustrated on the study of anharmonic oscillators (AO) with a potential V(x) = βx² + x^2m (m > 0). The method (Bervillier 2008 Nucl. Phys. B801 296) applies a priori to any ODE with two-point boundaries (one being located at infinity), the solution of which has (fixed) singularities in the complex plane of the independent variable x. A conformal mapping of a suitably chosen angular sector of the complex plane of x upon the unit disc centered at the origin makes convergent the transformed Taylor series of the generic solution so that the boundary condition at infinity can be easily imposed. In principle, this constraint, when applied on the logarithmic derivative of the wavefunction, determines the eigenvalues to an arbitrary level of accuracy. In practice, for β ≥ 0 or slightly negative, the accuracy of the results obtained is astonishingly large with regard to the modest computing power used. Various aspects of the method and comparisons with some seemingly similar methods, based also on expressing the solution as a Taylor series, are shortly reviewed, presented and discussed.