TelMeA is an asynchronous online community system that uses avatars to enact the messages of the users. We present an overview of the system, including the results of a usability study and its effect… (More)

The symmetry rule in propositional logic allows the exploitation of symmetries present in a problem. In the context of resolution, the rule enables the shortening of refutations by using symmetries… (More)

The method of analytic tableaux is employed in many introductory texts and has also been used quite extensively as a basis for automated theorem proving. In this paper, we discuss the complexity of… (More)

The “Todai Robot Project (Can a robot get into The University of Tokyo?)” was initiated by the National Institute of Informatics in 2011 as an AI grand challenge. The goal of the project was to… (More)

In Arai (1996), we introduced a new inference rule called permutation to propositional calculus and showed that cut-free Gentzen system LK (GCNF) with permutation (1) satis es the feasible subformula… (More)

We report on a project aiming at developing a system that solves a wide range of math problems written in natural language. In the system, formal analysis of natural language semantics is coupled… (More)

When David Hilbert started so called "Hilbert's program" (formalization of mathematics) in the early 20th century to give a solid foundation to mathematics, he unintentionally introduced the… (More)

We have been developing an end-to-end math problem solving system that accepts natural language input. The current paper focuses on how we analyze the problem sentences to produce logical forms. We… (More)