| ⊦ (⌜x⌝ + ⌜x0⌝ ) + ⌜nf⌝ = ⌜λ n. (n < # x ⊃ x[n];(n - # x < # x0 ⊃ x0[n - # x];nf(n - # x - # x0)))⌝ |
⊦ (⌜x⌝ + ⌜x0⌝ ) + ⌜nf⌝ = ⌜λ n. (n < # x ⊃ x[n];(n < # x0 + # x ⊃ x0[n - # x];nf(n - # x - # x0)))⌝
Used simplifier rules: n0 ≤ n ⊦ n - n0 < m ↔ n < m + n0; (s)% ⊦ m ≤ n ↔ ¬ n < m; (ss)