| reachS(source, N, n + 1), reach(source, b, m), m < 2 + n ⊦ reach<(source, b, n + 1), b ∈ V, ∃ a. b ∈ succ(a) ∧ reach(source, a, n) ∧ ¬ reach<(source, a, n), ∃ b1. ¬ ((∃ c. reach(source, c, n) ∧ b1 ∈ succ(c)) ∧ ¬ reach<(source, b1, n + 1) → b1 ∈ N), ∃ b1. ¬ (b1 ∈ V ↔ reach<(source, b1, n + 1) ∨ (∃ a. b1 ∈ succ(a) ∧ reach(source, a, n) ∧ ¬ reach<(source, a, n))) |
⊦ reach<(a, b, n) ↔ (∃ m. m < n ∧ reach(a, b, m))
reachS(source, N, n + 1), reach(source, b, m), m < 2 + n ⊦ ∃ m. m < n + 1 ∧ reach(source, b, m), b ∈ V, ∃ a. b ∈ succ(a) ∧ reach(source, a, n) ∧ ¬ reach<(source, a, n), ∃ b1. ¬ ((∃ c. reach(source, c, n) ∧ b1 ∈ succ(c)) ∧ ¬ reach<(source, b1, n + 1) → b1 ∈ N), ∃ b1. ¬ (b1 ∈ V ↔ reach<(source, b1, n + 1) ∨ (∃ a. b1 ∈ succ(a) ∧ reach(source, a, n) ∧ ¬ reach<(source, a, n)))
[[CONCRETESIMPRULES : ()], [EXTRATERMS : (n + 1, b, source)]]