| m ≤ # x ⊦ ⌜x⌝ + σ to m = ⌜x to m⌝ |
∀ m, σ. m ≤ # x0 → ⌜x0⌝ + σ to m = ⌜x0 to m⌝ , m ≤ #(a + x0) ⊦ ⌜a + x0⌝ + σ to m = ⌜a + x0 to m⌝
Used simplifier rules: empty: ⊦ ⌜[]⌝ = [];%empty-append: ⊦ [] + σ = σ;%append-assoc: ⊦ (σ + σ1) + σ2 = σ + σ1 + σ2;%to-zero: ⊦ σ to 0 = [];%to-zero-l: ⊦ x to 0 = [];%list freely generated by [], +;;%size-01: ⊦ # [] = 0; from specification list-data%lez-01: ⊦ m ≤ 0 ↔ m = 0; from specification nat