  The origin of brown dwarfs (BDs) is still an unsolved mystery. While the
standard model describes the formation of BDs and stars in a similar way recent
data on the multiplicity properties of stars and BDs show them to have
different binary distribution functions. Here we show that proper treatment of
these uncovers a discontinuity of the multiplicity-corrected mass distribution
in the very-low-mass star (VLMS) and BD mass regime. A continuous IMF can be
discarded with extremely high confidence. This suggests that VLMSs and BDs on
the one hand, and stars on the other, are two correlated but disjoint
populations with different dynamical histories. The analysis presented here
suggests that about one BD forms per five stars and that the BD-star binary
fraction is about 2%-3% among stellar systems.
