We consider the conductance of a one-dimensional wire interrupted by a
double-barrier structure allowing for a resonant level. Using the
electron-electron interaction strength as a small parameter, we are able to
build a non-perturbative analytical theory of the conductance valid in a broad
region of temperatures and for a variety of the barrier parameters. We find
that the conductance may have a non-monotonic crossover dependence on
temperature, specific for a resonant tunneling in an interacting electron
system.Comment: 4 pages. 2 figure