Project supported by the National Natural Science Foundation of China (Grant No. 19771045);Nationl High-Tech R&D Project (863) (Grant No. 863-306-ET06-01-2).
The minimal unsatisfiability problem is considered of the prepositional formulas in CNF which in the case of variablesx 1,?,x n consist ofn +k clauses including it,x 1 V ? Vx n and ?x 1 V ? V ?x n It is shown that whe...