| # x2 = n + 1, (H[r].nxt ' + x1).last = x2.last, # x1 = n + 1, path(H[r].nxt ' + x2, H), r ∈ H, reachable-1(H, H[r].nxt, r0), reachable-n(H, n, r0, x2.last), path(H[r].nxt ' + x1, H) ⊦ ∃ r1. reachable-1(H, H[r].nxt, r1) ∧ reachable-n(H, n, r1, x2.last), r = null, x2 = [] |
Used terms: r0