| perm(i ' + ints2, ints0 + ints1), ∀ ints0, ints1. perm(ints2, ints0 + ints1) → Π ints2 = Π ints0 * Π ints1 ⊦ i * Π ints2 = Π ints0 * Π ints1 |
⊦ perm(i ' + ints, ints0) ↔ ¬ ¬(i ∈ ints0 ∧ perm(ints, ints0 -1l i))
i ∈ ints0 + ints1 ∧ perm(ints2, (ints0 + ints1) -1l i), ∀ ints0, ints1. perm(ints2, ints0 + ints1) → Π ints2 = Π ints0 * Π ints1 ⊦ i * Π ints2 = Π ints0 * Π ints1
Used terms: ints0 + ints1, ints2, i