  In this paper we compare two proof systems for minimal entailment: a tableau
system OTAB and a sequent calculus MLK, both developed by Olivetti (1992). Our
main result shows that OTAB-proofs can be efficiently translated into
MLK-proofs, i.e; MLK p-simulates OTAB. The simulation is technically very
involved and answers an open question posed by Olivetti (1992) on the relation
between the two calculi. We also show that the two systems are exponentially
separated, i.e; there are formulas which have polynomial size MLK-proofs, but
require exponential-size OTAB- proofs.
