Admissible heuristic with multi-landmarks counting

Landmarks for a planning task are sub-goals that are necessarily made true at some time steps for any success plan. It is showed that the heuristic search with landmarks guiding has gained great success in 2008 IPC. Present landmark-counting heuristics are competitive until the complete causal landmarks have been extracted. Here, we propose an multi-path dependent heuristic which restricts the fact landmarks to be achieved from the current state during the search with considering the repeatedly appearance of action landmarks. Our cost-sharing heuristic is proved theoretically admissible and empirically efficient.