| m ≤ # x0, ∀ m, a. m < # x0 → a ∈ x0[m, a] ⊦ a ∈ (a0 ' + x0)[m, a] |
⊦ n ≠ 0 ∧ x ≠ [] → x[n, a] = x.first ' + x.rest[n -1, a]
m ≠ 0 ∧ a0 ' + x0 ≠ [], m ≤ # x0, ∀ m, a. m < # x0 → a ∈ x0[m, a] ⊦ a ∈ (a0 ' + x0).first ' + (a0 ' + x0).rest[m -1, a]
Used simplifier rules: put-zero: ⊦ (b ' + x)[0, a] = a + x;%e-01: ⊦ a ' + x ≠ []; from specification list%a: ⊦ (x + y) + z = x + y + z; from specification list%lez: ⊦ 0 ≤ m; from specification nat%c: ⊦ a + x = a ' + x; from specification list%in-06: ⊦ ¬ a ∈ b ' + x ↔ a ≠ b ∧ ¬ a ∈ x; from specification list Used terms: a, m, a0 ' + x0