| a ≠ a0, a0 < a, ∀ a. ins≤(a, x0) -1l a = x0 ⊦ a0 ' + (ins≤(a, x0) -1l a) = a0 ' + x0 |
a0 < a, ∀ a. ins≤(a, x0) -1l a = x0 ⊦ a = a0, ins≤(a, x0) -1l a = x0
Used simplifier rules: a: ⊦ (x + y) + z = x + y + z; from specification list%app-08: ⊦ a ' + x = a ' + y ↔ x = y; from specification list