The Mathematical Intelligencer

, Volume 8, Issue 1, pp 10–20 | Cite as

The four color proof suffices

  • K. Appel
  • W. Haken


Since no one else has communicated any other errors in the published unavoidability proof since 1976 we assume that a misunderstanding of the nature of Schmidt’s work was the source of those rumors that seem to have stimulated so much new interest in our work. We would certainly appreciate independent verification of the remaining 60 percent of our unavoidability proof and would be grateful for any information on further bookkeeping (or other) errors whenever such are found.* We have written computer programs preparatory to a thorough com puter verification of all of the material in the microfiche supplements. When this is completed we plan to publish (entirely on paper rather than on microfiche cards) an entire emended version of our original proof including theq-positive bookkeeping. At first thought one might think that we would miss the pleasures of discussing the latest rumors with our colleagues returning from meetings but further consideration leads us to believe that facts have never stopped the propagation of a good rumor and so nothing much will change.


Initial Charge Central Versus Independent Verification Connected Planar Graph Planar Triangulation 
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Copyright information

© Springer Science+Business Media, Inc. 1986

Authors and Affiliations

  • K. Appel
    • 1
  • W. Haken
    • 1
  1. 1.Department of MathematicsUniversity of Illinois UrbanaIllinois

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