We discuss a many-body Hamiltonian with two- and three-body interactio
ns in two dimensions introduced recently by Murthy, Bhaduri and Sen. A
part from an analysis of some exact solutions in the many-body system,
we analyse in detail the two-body problem which is completely solvabl
e. We show that the solution of the two-body problem reduces to solvin
g a known differential equation due to Heun. We show that the two-body
spectrum becomes remarkably simple for large interaction strengths an
d the level structure resembles that of the Landau levels. We also cla
rify the 'ultraviolet' regularization which is needed to define an inv
erse-square potential properly and discuss its implications for our mo
del.