Path: utzoo!utgpu!water!watmath!clyde!att!pacbell!ames!nrl-cmf!cmcl2!husc6!bloom-beacon!gatech!udel!burdvax!sdcrdcf!trwrb!aero!abbott From: abbott@aero.ARPA (Russell J. Abbott) Newsgroups: comp.ai Subject: Proof Checker Wanted Summary: Want a program that undergraduates can use to check proofs Keywords: proof checker Message-ID: <30133@aero.ARPA> Date: 12 May 88 18:55:39 GMT Reply-To: abbott@aerospace.aero.org (Russell J. Abbott) Organization: The Aerospace Corporation, El Segundo, CA Lines: 18 Does anyone have or know of a public domain, free, or cheap proof checker that can be used by undergraduates to write and check simple proofs. I'm teaching an automata theory and formal languages course, and the students are having a hard time formalizing their thinking. It would be nice if they could practice with an automated proof checker. A simple example problem is: prove that all strings in the set denoted by the regular expression (01 + 10)* have the same number of 0's as 1. The proof is straightforward by induction on the length of the string. The proof checker should have built into it knowledge of set notation, i.e., {X | p(X)}, strings, and of inductive proofs. It should also have a basic knowledge of simple arithmetic. Of course it also needs to be able to use results that are proved earlier or given to it as axioms. Thanks, -- Russ Abbott