| # nσ = ⌜n0⌝ + ⌜1⌝ , stutf(nσ), ¬(nσ[n0] + 1 ≠ 0 → (∃ m. ¬ n0 < m ∧ nσ[m] = nσ[n0] + 1 - 1)), ∀ n. ¬(n ≠ 0 → (∃ m. ¬ n0 < m ∧ nσ[m] = n - 1)) ⊦ |
# nσ = ⌜n0⌝ + ⌜1⌝ , stutf(nσ), ∀ n. ¬(n ≠ 0 → (∃ m. ¬ n0 < m ∧ nσ[m] = n - 1)) ⊦ ∃ m. ¬ n0 < m ∧ nσ[m] = nσ[n0]
Used simplifier rules: add-base: ⊦ n + 0 = n; from specification nat-basic2%add-01: ⊦ n ≤ m → m + n0 - n = (m - n) + n0; from specification nat%c: ⊦ m + n = n + m; from specification nat-basic2%a: ⊦ (m + n0) + n1 = m + n0 + n1; from specification nat-basic2%oz: ⊦ m + 1 ≠ 0; from specification nat-basic2