| stutf(nσ), ⌜m0⌝ + ⌜1⌝ < # nσ, n ≤ nσ[m0 + 1], ∀ nσ, n. stutf(nσ) ∧ ⌜m0⌝ < # nσ ∧ n ≤ nσ[m0] → (∃ m1. m1 ≤ m0 ∧ nσ[m1] = n), ⌜m0⌝ < # nσ ∧ n ≤ nσ[m0] → m ≤ m0 ∧ nσ[m] = n ⊦ ∃ m. m ≤ m0 + 1 ∧ nσ[m] = n |
stutf(nσ), ⌜m0⌝ + ⌜1⌝ < # nσ, n ≤ nσ[m0 + 1], ∀ nσ, n. stutf(nσ) ∧ ⌜m0⌝ < # nσ ∧ n ≤ nσ[m0] → (∃ m1. m1 ≤ m0 ∧ nσ[m1] = n) ⊦ ⌜m0⌝ < # nσ ∧ n ≤ nσ[m0], ∃ m. m ≤ m0 + 1 ∧ nσ[m] = n
m ≤ m0 ∧ nσ[m] = n, stutf(nσ), ⌜m0⌝ + ⌜1⌝ < # nσ, n ≤ nσ[m0 + 1], ∀ nσ, n. stutf(nσ) ∧ ⌜m0⌝ < # nσ ∧ n ≤ nσ[m0] → (∃ m1. m1 ≤ m0 ∧ nσ[m1] = n) ⊦ ∃ m. m ≤ m0 + 1 ∧ nσ[m] = n