| b ∈ succ((a ' + y) .last), reach(a, (a ' + y) .last, # y), path(a ' + y) ⊦ succ((a ' + y) .last) = ∅, # succ((a ' + y) .last) = 0, ∃ x0. path(x0) ∧ # x0 = 2 + # y ∧ x0 .first = a ∧ x0 .last = b |
y = [], b ∈ succ((a ' + y) .last), reach(a, (a ' + y) .last, # y), path(a ' + y) ⊦ succ((a ' + y) .last) = ∅, # succ((a ' + y) .last) = 0, ∃ x0. path(x0) ∧ # x0 = 2 + # y ∧ x0 .first = a ∧ x0 .last = b
b ∈ succ((a ' + y) .last), reach(a, (a ' + y) .last, # y), path(a ' + y) ⊦ y = [], succ((a ' + y) .last) = ∅, # succ((a ' + y) .last) = 0, ∃ x0. path(x0) ∧ # x0 = 2 + # y ∧ x0 .first = a ∧ x0 .last = b
[[CONCRETESIMPRULES : ()], [EXTRAFMAS : (y = [])]]