| kar[m].key < kar[0].key, m < n, heap-order(kar, n), n ≤ # kar ⊦ m = 0, n = 0 |
m < n0 +1, kar[m].key < kar[0].key, heap-order(kar, n0 +1), n0 +1 ≤ # kar, ∀ kar, m. kar[m].key < kar[0].key ∧ m < n0 ∧ heap-order(kar, n0) ∧ n0 ≤ # kar → m = 0 ∨ n0 = 0 ⊦ n0 +1 = 0, m = 0
Used simplifier rules: nat freely generated by 0, +1;;