Derived clause in a DRUP proof.
Derived clause in a DRUP proof.
The clause is not only required to be a consequence of the previous clauses in the proof, but also RUP (a strictly stronger requirement):
Given a set of clauses Γ and a clause C, then C has the property RUP with regard to Γ iff Γ, ¬C can be refuted with only unit propagation.
Forgets a clause in a DRUP proof.
Forgets a clause in a DRUP proof.
This inference is not necessary for completeness, it is mainly a performance optimization since it speeds up the unit propagation in DrupDerive.
Input clause in a DRUP proof.
DRUP proof.
DRUP proof.
A DRUP proof consists of a sequence of clauses. Each clause is either a DrupInput, a DrupDerive, or a DrupForget.