A similarity transformation is constructed, through which a system of parti
cles interacting with inverse-square two-body and harmonic potentials in on
e dimension can be mapped identically to a set of free harmonic oscillators
. This equivalence provides a straightforward method to find the complete s
et of eigenfunctions, the exact constants of motion, and a linens W1+infini
ty algebra associated with this model. It is also demonstrated that a large
class of models with long-range interactions, both in one and higher dimen
sions can be made equivalent to decoupled oscillators. [S0163-1829(99)51404
-5].