| xs1 + prefixn(# xs1 + 1 - # xs1, ys) = prefixn(# xs1 + 1, xs0), # xs1 ≤ # xs0, # xs1 + # ys ≤ # xs0, # xs1 ≤ # xs1 + 1, ys = [] ∨ # ys = # xs1 + 1 ⊦ xs1 = prefixn(# xs1, xs0) |
xs1 + prefixn(1, ys) = prefixn(# xs1 + 1, xs0), # xs1 + # ys ≤ # xs0, # xs1 ≤ # xs0, ys = [] ∨ # ys = # xs1 + 1 ⊦ xs1 = prefixn(# xs1, xs0)
Used simplifier rules: ⊦ m ≤ m + n; (s)%c: ⊦ m + n = n + m; from specification nat-basic%a: ⊦ (m + n0) + n1 = m + n0 + n1; from specification nat-basic% ⊦ m + n - m = n; (s)