| path(r ' + x, H) ⊦ x = [], r = null, ∃ n. reachable-n(H, n, r, x.last) |
∀ r, H. path(r ' + x0, H) → x0 = [] ∨ r = null ∨ (∃ n. reachable-n(H, n, r, x0.last)), path(r ' + (r0 + x0), H) ⊦ r0 + x0 = [], r = null, ∃ n. reachable-n(H, n, r, (r0 + x0).last)
Used simplifier rules: reflist freely generated by [], +;;