| lfgen(0)(0) = a ', lfgen(n1)(m0) = lfgen(n0)(m0), m0 < n1, n1 ≤ n0, m0 < n0, lfgen(n1)(0) = a ' ∧ (∀ m. m < n1 → lfgen(n1)(m + 1) = nextl(m, lfgen(n1)(m).last) ∧ lfgen(n1)(m) ≠ []), ∀ n. lfgen(n)(0) = a ' ∧ (∀ m. m < n → lfgen(n)(m + 1) = nextl(m, lfgen(n)(m).last) ∧ lfgen(n)(m) ≠ []), ∀ n, a. nextl(n, a) ≠ [] ⊦ lfgen(n1)(m0 + 1) = lfgen(n0)(m0 + 1), n1 = 0, n0 = 0 |
lfgen(0)(0) = a ', lfgen(n1)(m0) = lfgen(n0)(m0), lfgen(n1)(0) = a ', m0 < n1, n1 ≤ n0, m0 < n0, ∀ m. m < n1 → lfgen(n1)(m + 1) = nextl(m, lfgen(n1)(m).last) ∧ lfgen(n1)(m) ≠ [], ∀ n. lfgen(n)(0) = a ' ∧ (∀ m. m < n → lfgen(n)(m + 1) = nextl(m, lfgen(n)(m).last) ∧ lfgen(n)(m) ≠ []), ∀ n, a. nextl(n, a) ≠ [] ⊦ lfgen(n1)(m0 + 1) = lfgen(n0)(m0 + 1), n1 = 0, n0 = 0