| b ∈ succ(c), reach(a, c, n0), ∀ a, b. reach(a, b, n0) ↔ (∃ x. path(x) ∧ # x = n0 + 1 ∧ x .first = a ∧ x .last = b) ⊦ succ(c) = ∅, # succ(c) = 0, ∃ x. path(x) ∧ # x = 2 + n0 ∧ x .first = a ∧ x .last = b |
b ∈ succ(c), reach(a, c, n0), reach(a, c, n0) ↔ (∃ x. path(x) ∧ # x = n0 + 1 ∧ x .first = a ∧ x .last = c) ⊦ succ(c) = ∅, # succ(c) = 0, ∃ x. path(x) ∧ # x = 2 + n0 ∧ x .first = a ∧ x .last = b
[[CONCRETESIMPRULES : ()], [EXTRATERMS : (a, c)]]