| pos(a, x0) + 1 < # x0, a ∈ x0, m + 1 < # x0, pos(a, x0) ≤ m, ∀ a1, n0. a1 ∈ x0 ∧ n0 + 1 < # x0 → (x0 \ a1 ')[n0] = (n0 < pos(a1, x0) ⊃ x0[n0];x0[n0 + 1]) ⊦ x0 = [], (x0 \ a ')[m] = x0[m + 1], a0 ∈ x0, dups(x0) |
Used simplifier rules: le-ls-simp: ⊦ m ≤ n → (n < m ↔ false); from specification nat Used terms: a, m