Logical Methods in Computer Science Volume 15, Issue 1, 2019, pp. 34:1–34:37 Submitted Jan. 24, 2018 https://lmcs.episciences.org/ Published Mar. 29, 2019 COMPUTER-ASSISTED PROVING OF COMBINATORIAL CONJECTURES OVER FINITE DOMAINS: A CASE STUDY OF A CHESS CONJECTURE PREDRAG JANICIˇ C´ a, FILIP MARIC´ a, AND MARKO MALIKOVIC´ b a Faculty of Mathematics, University of Belgrade, Serbia e-mail address: fjanicic,fi
[email protected] b Faculty of Humanities and Social Sciences, University of Rijeka, Croatia e-mail address: marko@ffri.hr Abstract. There are several approaches for using computers in deriving mathematical proofs. For their illustration, we provide an in-depth study of using computer support for proving one complex combinatorial conjecture { correctness of a strategy for the chess KRK endgame. The final, machine verifiable result presented in this paper is that there is a winning strategy for white in the KRK endgame generalized to n × n board (for natural n greater than 3). We demonstrate that different approaches for computer-based theorem proving work best together and in synergy and that the technology currently available is powerful enough for providing significant help to humans deriving some complex proofs. 1. Introduction Over the last several decades, automated and interactive theorem provers have made huge advances which changed the mathematical landscape significantly. Theorem provers are already widely used in many areas of mathematics and computer science, and there are already proofs of many extremely complex theorems developed within proof assistants and with many lemmas proved or checked automatically [25, 31, 33]. We believe there are changes still to come, changes that would make new common mathematical practices and proving process will be more widely supported by tools that automatically and reliably prove some conjectures and even discover new theorems.