  In this paper, we take advantage of the Mellin type derivative to produce
some new families of polynomials whose coefficients involve r-Lah numbers. One
of these polynomials leads to rediscover many of the identities of r-Lah
numbers. We show that some of these polynomials and hyperharmonic numbers are
closely related. Taking into account of these connections, we reach several
identities for harmonic and hyperharmonic numbers.
