| ordered≤(a0 ' + y), ordered≤(a ' + x1), ∀ x. ordered≤(x) ∧ (x ≠ [] → ¬ x.first < x1.last) → ordered≤(x1 + x) ⊦ x1 = [], ordered≤(a ' + x1 + a0 ' + y), a0 < x1.last |
ordered≤(a0 ' + y), ordered≤(a ' + x1), ordered≤(a0 ' + y) ∧ (a0 ' + y ≠ [] → ¬ (a0 ' + y).first < x1.last) → ordered≤(x1 + a0 ' + y), ∀ x. ordered≤(x) ∧ (x ≠ [] → ¬ x.first < x1.last) → ordered≤(x1 + x) ⊦ x1 = [], ordered≤(a ' + x1 + a0 ' + y), a0 < x1.last
Used terms: a0 ' + y