  The singular parametric oscillators obtained from the one-parameter Darboux
deformation/transformation effected upon the classical harmonic oscillator are
introduced and discussed in some detail using sin(omega_0 t) and cos(omega_0 t)
as seed solutions. The corresponding Ermakov-Lewis integrability problem of
these parametric oscillators is also studied. It is shown that the
Ermakov-Lewis invariants do not depend on the deformation parameter.
