We consider the minimal unsatisfiability problem for propositional formulas
over n variables with n + k clauses for fixed k. We will show that in case
of at most n clauses no formula is minimal unsatisfiable. For n + 1 clause
s the minimal unsatisfiability problem is solvable in quadratic time. Furth
er, we present a characterization of minimal unsatisfiable formulas with n
+ 1 clauses in terms of a certain form of matrices.