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https://github.com/coq-community/templates to regenerate.\n---\u003e\n# The Four Color Theorem\n\n[![Docker CI][docker-action-shield]][docker-action-link]\n[![Contributing][contributing-shield]][contributing-link]\n[![Code of Conduct][conduct-shield]][conduct-link]\n[![Zulip][zulip-shield]][zulip-link]\n\n[docker-action-shield]: https://github.com/coq-community/fourcolor/actions/workflows/docker-action.yml/badge.svg?branch=master\n[docker-action-link]: https://github.com/coq-community/fourcolor/actions/workflows/docker-action.yml\n\n[contributing-shield]: https://img.shields.io/badge/contributions-welcome-%23f7931e.svg\n[contributing-link]: https://github.com/coq-community/manifesto/blob/master/CONTRIBUTING.md\n\n[conduct-shield]: https://img.shields.io/badge/%E2%9D%A4-code%20of%20conduct-%23f15a24.svg\n[conduct-link]: https://github.com/coq-community/manifesto/blob/master/CODE_OF_CONDUCT.md\n\n[zulip-shield]: https://img.shields.io/badge/chat-on%20zulip-%23c1272d.svg\n[zulip-link]: https://coq.zulipchat.com/#narrow/stream/237663-coq-community-devs.20.26.20users\n\n\n\nThis library contains a formal proof of the Four Color Theorem in Coq,\nalong with the theories needed to support stating and then proving the Theorem.\nThis includes an axiomatization of the setoid of classical real numbers,\nbasic plane topology definitions, and a theory of combinatorial hypermaps.\n\n## Meta\n\n- Author(s):\n  - Georges Gonthier (initial)\n- Coq-community maintainer(s):\n  - Yves Bertot ([**@ybertot**](https://github.com/ybertot))\n- License: [CeCILL-B](LICENSE)\n- Compatible Coq versions: 8.20 or later\n- Additional dependencies:\n  - [MathComp ssreflect 2.5.0 or later](https://math-comp.github.io)\n  - [MathComp algebra](https://math-comp.github.io)\n  - [Hierarchy Builder](https://github.com/math-comp/hierarchy-builder) 1.5.0 or later\n- Coq namespace: `fourcolor`\n- Related publication(s):\n  - [Formal Proof—The Four-Color Theorem](https://www.ams.org/notices/200811/tx081101382p.pdf) \n  - [A computer-checked proof of the Four Color Theorem](https://inria.hal.science/hal-04034866/document) \n\n## Building and installation instructions\n\nThe easiest way to install the latest released version of The Four Color Theorem\nis via [opam](https://opam.ocaml.org/doc/Install.html):\n\n```shell\nopam repo add coq-released https://coq.inria.fr/opam/released\nopam install coq-fourcolor\n```\n\nIf you are only interested in the formalization of real numbers, you can install\nit separately:\n\n```shell\nopam repo add coq-released https://coq.inria.fr/opam/released\nopam install coq-fourcolor-reals\n```\n\nTo instead build and install the whole project manually from the repository, do:\n\n``` shell\ngit clone https://github.com/coq-community/fourcolor.git\ncd fourcolor\nmake   # or make -j \u003cnumber-of-cores-on-your-machine\u003e \nmake install\n```\n\n## Documentation\n\nThe [Four Color Theorem](https://en.wikipedia.org/wiki/Four_color_theorem) (Appel \u0026 Haken, 1976) is a landmark result of graph theory.\n\nThe formal proof is based on the [Mathematical Components](https://github.com/math-comp/math-comp) library.\n","project_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Frocq-community%2Ffourcolor","html_url":"https://awesome.ecosyste.ms/projects/github.com%2Frocq-community%2Ffourcolor","lists_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Frocq-community%2Ffourcolor/lists"}