Exercise logic.propositional.dnf.unicode

Description
Proposition to DNF (unicode support)

Derivation

Final term is not finished

¬(q → p) ↔ (((¬r ∧ ¬s) ∨ r ∨ ¬s) ∧ (s ∨ (¬r ∧ ¬s) ∨ ¬s))