| x1 + r2 ' + x2 = x + H[(r0 ' + y).last].nxt ' + (r0 ' + y).butlast, ((r0 ' + y).last ' + x0).last = (r ' + x).last, (r ' + x1).last = (r ' + x).last, (r ' + x).last ∈ H, path(r ' + x1, H), path(r ' + x + H[(r0 ' + y).last].nxt ', H), path(r ' + x1 + r2 ' + x2 + (r0 ' + y).last ', H), H[(r0 ' + y).last].nxt ∈ H, (r0 ' + y).last ∈ H, path((r0 ' + y).last ' + x0, H), (r0 ' + y).last = H[(r0 ' + y).last].nxt ∨ (r0 ' + y).last = r0 ∨ (r0 ' + y).last ∈ y ⊦ H[(r0 ' + y).last].nxt = null, (r0 ' + y).last = r, r = r2, r2 = (r0 ' + y).last, (r0 ' + y).last ∈ x, (r0 ' + y).last ∈ x0, dups(x0), r ∈ x1, r ∈ x2, r2 ∈ x1, r2 ∈ x2, (r0 ' + y).last ∈ x1, (r0 ' + y).last ∈ x2, dups(x1 + x2), dups(x1), dups(x2) |
⊦ x0 ≠ [] → (x1 + x0).butlast = x1 + x0.butlast
¬ y ≠ [], x1 + r2 ' + x2 = x + H[(r0 ' + y).last].nxt ' + (r0 ' + y).butlast, ((r0 ' + y).last ' + x0).last = (r ' + x).last, (r ' + x1).last = (r ' + x).last, (r ' + x).last ∈ H, path(r ' + x1, H), path(r ' + x + H[(r0 ' + y).last].nxt ', H), path(r ' + x1 + r2 ' + x2 + (r0 ' + y).last ', H), H[(r0 ' + y).last].nxt ∈ H, (r0 ' + y).last ∈ H, path((r0 ' + y).last ' + x0, H), (r0 ' + y).last = H[(r0 ' + y).last].nxt ∨ (r0 ' + y).last = r0 ∨ (r0 ' + y).last ∈ y ⊦ H[(r0 ' + y).last].nxt = null, (r0 ' + y).last = r, r = r2, r2 = (r0 ' + y).last, (r0 ' + y).last ∈ x, (r0 ' + y).last ∈ x0, dups(x0), r ∈ x1, r ∈ x2, r2 ∈ x1, r2 ∈ x2, (r0 ' + y).last ∈ x1, (r0 ' + y).last ∈ x2, dups(x1 + x2), dups(x1), dups(x2)
y ≠ [], x1 + r2 ' + x2 = x + H[(r0 ' + y).last].nxt ' + r0 ' + y.butlast, ((r0 ' + y).last ' + x0).last = (r ' + x).last, (r ' + x1).last = (r ' + x).last, (r ' + x).last ∈ H, path(r ' + x1, H), path(r ' + x + H[(r0 ' + y).last].nxt ', H), path(r ' + x1 + r2 ' + x2 + (r0 ' + y).last ', H), H[(r0 ' + y).last].nxt ∈ H, (r0 ' + y).last ∈ H, path((r0 ' + y).last ' + x0, H), (r0 ' + y).last = H[(r0 ' + y).last].nxt ∨ (r0 ' + y).last = r0 ∨ (r0 ' + y).last ∈ y ⊦ H[(r0 ' + y).last].nxt = null, (r0 ' + y).last = r, r = r2, r2 = (r0 ' + y).last, (r0 ' + y).last ∈ x, (r0 ' + y).last ∈ x0, dups(x0), r ∈ x1, r ∈ x2, r2 ∈ x1, r2 ∈ x2, (r0 ' + y).last ∈ x1, (r0 ' + y).last ∈ x2, dups(x1 + x2), dups(x1), dups(x2)
Used terms: y, r0 '