| ce.nxt = null, path(r ' + x, H[r2, ce]), (r ' + x).last ∈ H, (r ' + x).last ∈ H[r2, ce] ⊦ r2 ∈ H, path(r ' + x, H) |
∀ ce, r, H, r2. ce.nxt = null ∧ path(r ' + x0, H[r2, ce]) ∧ (r ' + x0).last ∈ H ∧ (r ' + x0).last ∈ H[r2, ce] → r2 ∈ H ∨ path(r ' + x0, H), ce.nxt = null, path(r ' + (r0 + x0), H[r2, ce]), (r ' + (r0 + x0)).last ∈ H, (r ' + (r0 + x0)).last ∈ H[r2, ce] ⊦ r2 ∈ H, path(r ' + (r0 + x0), H)
Used simplifier rules: path-one: ⊦ path(r ', H) ↔ ¬ ¬(r ∈ H ∧ r ≠ null);%reflist freely generated by [], +;;%app: ⊦ x0 + [] = x0; from specification list[reflist]%a: ⊦ (x0 + x1) + x2 = x0 + x1 + x2; from specification list[reflist]%l: ⊦ r '.last = r; from specification list-last[reflist]