  We prove the equidistribution of several multistatistics over some classes of
permutations avoiding a $3$-length pattern. We deduce the equidistribution, on
the one hand of inv and foze" statistics, and on the other hand that of maj and
makl statistics, over these classes of pattern avoiding permutations. Here inv
and maj are the celebrated Mahonian statistics, foze" is one of the statistics
defined in terms of generalized patterns in the 2000 pioneering paper of Babson
and Steingr\'imsson, and makl is one of the statistics defined by Clarke,
Steingr\'imsson and Zeng in 1997. These results solve several conjectures posed
by Amini in 2018.
