| n0 < # buf1, ∀ n. n < # buf0 + # buf1 → (buf0 + buf1)[n] = empty ⊦ buf1[n0] = empty |
n0 < # buf1, ∀ n. n < # buf0 + # buf1 → (buf0 + buf1)[n] = empty ⊦ buf1[n0] = empty
Used simplifier rules: ⊦ m < n → n ≠ 0; (s)%f: ⊦ m < n → n ≠ 0; (forward) from specification nat-basic