Abstract
The paper concerns an AND/OR-tree search algorithm to solve hard problems. Proof-number search is a well-known powerful search algorithm for that purpose. Its depth-first variants such as PN*, PDS, and df-pn work very well, in particular in the domain of shogi mating problems. However, there are still possible drawbacks. The most prevailing one is the double-counting problem. To handle this problem the paper proposes a new search idea using proof number and branching factor as search estimators. We call the new method Weak Proof-Number Search. The experiments performed in the domain of shogi and Othello show that the proposed search algorithm is potentially more powerful than the original proof-number search or its depth-first variants.
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Ueda, T., Hashimoto, T., Hashimoto, J., Iida, H. (2008). Weak Proof-Number Search. In: van den Herik, H.J., Xu, X., Ma, Z., Winands, M.H.M. (eds) Computers and Games. CG 2008. Lecture Notes in Computer Science, vol 5131. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-540-87608-3_15
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DOI: https://doi.org/10.1007/978-3-540-87608-3_15
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