Proof Pearl: a Formal Proof of Higman’s Lemma in ACL2

Journal of Automated Reasoning - Tập 47 - Trang 229-250 - 2010
Francisco Jesús Martín-Mateos1, José Luis Ruiz-Reina1, José Antonio Alonso1, María José Hidalgo1
1Computational Logic Group, Department of Computer Science and Artificial Intelligence, University of Seville, E.T.S.I. Informática, Sevilla, Spain

Tóm tắt

Higman’s lemma is an important result in infinitary combinatorics, which has been formalized in several theorem provers. In this paper we present a formalization and proof of Higman’s Lemma in the ACL2 theorem prover. Our formalization is based on a proof by Murthy and Russell, where the key termination argument is justified by the multiset relation induced by a well-founded relation. To our knowledge, this is the first mechanization of this proof.

Tài liệu tham khảo

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