| m < # x ⊦ a ∈ x[m, a] -1l a ↔ a ∈ x, x[m] = a |
m < #(a0 + x0), ∀ m, a. m < # x0 → (a ∈ x0[m, a] -1l a ↔ a ∈ x0) ∨ x0[m] = a ⊦ a ∈ (a0 + x0)[m, a] -1l a ↔ a ∈ a0 + x0, (a0 + x0)[m] = a
Used simplifier rules: list freely generated by [], +;;% ⊦ ¬ a ∈ []; (s)% ⊦ # [] = 0; (s)% ⊦ ¬ n < 0; (s)