⊦ odd(i) ↔ ¬ even(i)
⊦ (¬ even(i) ∨ ¬ even(j)) ∧ (even(i) ∨ ¬ ¬ even(j)) ↔ ¬ even(i) ∧ even(j) ∨ even(i) ∧ ¬ even(j)
Used terms: j