Reducibility in the Four-Color Theorem

Abstract

In [J. Combin. Theory Ser. B 70 (1997), 2-44] we gave a simplified proof of the Four-Color Theorem. The proof is computer-assisted in the sense that for two lemmas in the article we did not give proofs, and instead asserted that we have verified those statements using a computer. Here we give additional details for one of those lemmas, and we include the original computer programs and data as "ancillary files" accompanying this submission.

8 pages, 2 ancillary files. These files were originally posted on an anonymous ftp server and later (after the server's shutdown) were relocated to the last author's website