Abstract
We define by a 2DNF formula a Boolean map from n bits to n+1 bits such that in any propositional proof system for which the PHP principle is hard, it is hard to prove about any n+1 string that it is outside of the range of the map.
We define by a 2DNF formula a Boolean map from n bits to n+1 bits such that in any propositional proof system for which the PHP principle is hard, it is hard to prove about any n+1 string that it is outside of the range of the map.