| m ≤ # x0, ∀ m, a, b. m < # x0 → (a ∈ x0[m, b] ↔ a = b ∨ a ∈ x0 -1l x0[m]) ⊦ (a0 ' + x0)[m] = a0, a ∈ (a0 ' + x0)[m, b] ↔ a = b ∨ a = a0 ∨ a ∈ x0 -1l (a0 ' + x0)[m] |
⊦ n ≠ 0 ∧ x ≠ [] → x[n, a] = x.first ' + x.rest[n -1, a]
m ≠ 0 ∧ a0 ' + x0 ≠ [], m ≤ # x0, ∀ m, a, b. m < # x0 → (a ∈ x0[m, b] ↔ a = b ∨ a ∈ x0 -1l x0[m]) ⊦ (a0 ' + x0)[m] = a0, a ∈ (a0 ' + x0).first ' + (a0 ' + x0).rest[m -1, b] ↔ a = b ∨ a = a0 ∨ a ∈ x0 -1l (a0 ' + x0)[m]
Used simplifier rules: put-zero: ⊦ (b ' + x)[0, a] = a + x;%get-zero-01: ⊦ (a ' + x)[0] = a;%in-04: ⊦ a ∈ x ∧ a ≠ b → a ∈ x -1l b;%del1-in: ⊦ a ≠ b → (a ∈ x -1l b ↔ a ∈ x);%e-01: ⊦ a ' + x ≠ []; from specification list%a: ⊦ (x + y) + z = x + y + z; from specification list%c: ⊦ a + x = a ' + x; from specification list%in-01: ⊦ a ≠ b → (a ∈ b ' + x ↔ a ∈ x); from specification list%in-rec: ⊦ a ∈ b ' + x ↔ ¬ ¬(a = b ∨ a ∈ x); from specification list Used terms: b, m, a0 ' + x0