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color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2011/03/clef-and-pipes-maps-v2.png</image:loc><image:title>clef-and-pipes-maps-v2</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2011/02/three-arbitrary-colors.png</image:loc><image:title>three-arbitrary-colors</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2011/02/maps-of-13-faces-01.png</image:loc><image:title>maps-of-13-faces-01</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2011/02/maps-and-graphs.png</image:loc><image:title>maps-and-graphs</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2011/02/layering-properties.png</image:loc><image:title>layering-properties</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2011/02/f5-maps-not-in-cluster.png</image:loc><image:title>F5-maps-not-in-cluster</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2011/02/f5-cluster.png</image:loc><image:title>F5-cluster</image:title><image:caption>Four color theorem</image:caption></image:image><lastmod>2025-01-11T20:37:26+00:00</lastmod><changefreq>weekly</changefreq><priority>0.6</priority></url><url><loc>https://four-color-theorem.com/2019/09/09/zoom-on-a-planar-graph-10000-nodes-three-edge-tait-colored/</loc><lastmod>2025-01-11T18:23:25+00:00</lastmod><changefreq>monthly</changefreq></url><url><loc>https://four-color-theorem.com/2022/08/22/non-hamiltonian-3-regular-planar-graphs-tait-coloring-and-kempe-loops-what-else/</loc><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2022/08/map.barnette-bosacc81k-lederberg.planar-colored-loops-vertical.jpg</image:loc><image:title>map.barnette-bosacc81k-lederberg.planar-colored-loops-vertical</image:title></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2022/08/map.barnette-bosacc81k-lederberg.planar-colored-loops.jpg</image:loc><image:title>map.barnette-bosacc81k-lederberg.planar-colored-loops</image:title></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2022/08/map.barnette-bosacc81k-lederberg.planar-colored.jpg</image:loc><image:title>map.barnette-bosacc81k-lederberg.planar-colored</image:title></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2022/08/image-2.png</image:loc><image:title>image-2</image:title></image:image><lastmod>2025-01-11T18:22:40+00:00</lastmod><changefreq>monthly</changefreq></url><url><loc>https://four-color-theorem.com/open-points-and-notes/searching-for-t0/</loc><lastmod>2025-01-11T18:14:30+00:00</lastmod><changefreq>weekly</changefreq><priority>0.6</priority></url><url><loc>https://four-color-theorem.com/open-points-and-notes/conversion-of-h-and-a-first-steps/</loc><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2011/02/tutte-rectangles-colored-with-cardinalities.png</image:loc><image:title>tutte-rectangles-colored-with-cardinalities</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2011/02/tutte-rectangles-colored.png</image:loc><image:title>tutte-rectangles-colored</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2011/02/tutte.png</image:loc><image:title>tutte</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2011/02/from-wikipedia-01-rectangles-stefanutti.png</image:loc><image:title>from-wikipedia-01-rectangles-stefanutti</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2011/02/from-wikipedia-01-numbered.png</image:loc><image:title>from-wikipedia-01-numbered</image:title><image:caption>Four color theorem</image:caption></image:image><lastmod>2025-01-11T18:08:58+00:00</lastmod><changefreq>weekly</changefreq><priority>0.6</priority></url><url><loc>https://four-color-theorem.com/open-points-and-notes/conversion-of-famous-maps/</loc><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2011/03/potential-criminals-circles-b-colored.png</image:loc><image:title>potential-criminals-circles-b-colored</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2011/03/potential-criminals.png</image:loc><image:title>potential-criminals</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2011/02/tutte-circles-colored.png</image:loc><image:title>tutte-circles-colored</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2011/02/from-wikipedia-01-circles-stefanutti.png</image:loc><image:title>from-wikipedia-01-circles-stefanutti</image:title><image:caption>Four color theorem</image:caption></image:image><lastmod>2025-01-11T18:05:33+00:00</lastmod><changefreq>weekly</changefreq><priority>0.6</priority></url><url><loc>https://four-color-theorem.com/open-points-and-notes/license/</loc><lastmod>2025-01-11T18:04:27+00:00</lastmod><changefreq>weekly</changefreq><priority>0.6</priority></url><url><loc>https://four-color-theorem.com/open-points-and-notes/simplify-f4-faces-first-version/</loc><lastmod>2025-01-11T18:01:06+00:00</lastmod><changefreq>weekly</changefreq><priority>0.6</priority></url><url><loc>https://four-color-theorem.com/open-points-and-notes/k4-and-different-four-colorings/</loc><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2011/04/different-coloring.png</image:loc><image:title>different-coloring</image:title><image:caption>Four color theorem</image:caption></image:image><lastmod>2025-01-11T17:57:46+00:00</lastmod><changefreq>weekly</changefreq><priority>0.6</priority></url><url><loc>https://four-color-theorem.com/2019/09/06/konigsberg-7-5-bridges/</loc><lastmod>2025-01-10T22:27:39+00:00</lastmod><changefreq>monthly</changefreq></url><url><loc>https://four-color-theorem.com/me/</loc><lastmod>2025-01-10T22:04:55+00:00</lastmod><changefreq>weekly</changefreq><priority>0.6</priority></url><url><loc>https://four-color-theorem.com/links/</loc><lastmod>2025-01-09T22:26:27+00:00</lastmod><changefreq>weekly</changefreq><priority>0.6</priority></url><url><loc>https://four-color-theorem.com/2011/02/08/just-another-site-about-the-four-color-theorem/</loc><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2011/02/map-15-rectangles.png</image:loc><image:title>map-15-rectangles</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2011/02/map-15-circles.png</image:loc><image:title>map-15-circles</image:title><image:caption>Four color theorem</image:caption></image:image><lastmod>2025-01-09T22:21:26+00:00</lastmod><changefreq>monthly</changefreq></url><url><loc>https://four-color-theorem.com/2011/03/24/four-color-theorem-music-is-on/</loc><lastmod>2025-01-09T22:13:00+00:00</lastmod><changefreq>monthly</changefreq></url><url><loc>https://four-color-theorem.com/2011/04/18/four-color-theorem-recap/</loc><lastmod>2025-01-09T22:11:09+00:00</lastmod><changefreq>monthly</changefreq></url><url><loc>https://four-color-theorem.com/spiral-chains/</loc><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2012/04/map-example.png</image:loc><image:title>map-example</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2012/02/spiral-chains-by-scanning-the-image.png</image:loc><image:title>spiral-chains-by-scanning-the-image</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2012/02/map-12-spiral-chain-hamiltonian.png</image:loc><image:title>map-12-spiral-chain-hamiltonian</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2012/02/map-30-spiral-chains.png</image:loc><image:title>map-30-spiral-chains</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2012/02/spiral-chains.png</image:loc><image:title>spiral-chains</image:title><image:caption>Four color theorem</image:caption></image:image><lastmod>2025-01-09T22:08:39+00:00</lastmod><changefreq>weekly</changefreq><priority>0.6</priority></url><url><loc>https://four-color-theorem.com/2012/03/02/four-color-theorem-java-application-update/</loc><lastmod>2025-01-09T22:07:02+00:00</lastmod><changefreq>monthly</changefreq></url><url><loc>https://four-color-theorem.com/2012/05/22/four-color-theorem-cahit-spiral-chains-step-two/</loc><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2012/05/spiral-chain-example-01.png</image:loc><image:title>spiral-chain-example-01</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2012/05/spiral-chain-example-02.png</image:loc><image:title>spiral-chain-example-02</image:title><image:caption>Four color theorem</image:caption></image:image><lastmod>2025-01-09T22:04:48+00:00</lastmod><changefreq>monthly</changefreq></url><url><loc>https://four-color-theorem.com/2013/01/26/four-color-theorem-simplified-maps-and-fullerenes/</loc><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2013/01/graph-16-3.png</image:loc><image:title>graph-16-3</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2013/01/graph-16-2.png</image:loc><image:title>graph-16-2</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2013/01/graph-16-1.png</image:loc><image:title>graph-16-1</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2013/01/graph-15.png</image:loc><image:title>graph-15</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2013/01/graph-14.png</image:loc><image:title>graph-14</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2013/01/graph-12.png</image:loc><image:title>graph-12</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2013/01/16-3.png</image:loc><image:title>16-3</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2013/01/16-2.png</image:loc><image:title>16-2</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2013/01/16-1.png</image:loc><image:title>16-1</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2013/01/15.png</image:loc><image:title>15</image:title><image:caption>Four color theorem</image:caption></image:image><lastmod>2025-01-09T22:03:30+00:00</lastmod><changefreq>monthly</changefreq></url><url><loc>https://four-color-theorem.com/2016/10/16/four-color-theorem-a-fast-algorithm/</loc><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2016/10/test-1996-vertices-2994-edges.png</image:loc><image:title>test-1996-vertices-2994-edges</image:title><image:caption>Four color theorem</image:caption></image:image><lastmod>2025-01-09T22:01:59+00:00</lastmod><changefreq>monthly</changefreq></url><url><loc>https://four-color-theorem.com/2013/02/12/four-color-theorem-new-video-and-new-software/</loc><lastmod>2025-01-09T22:00:51+00:00</lastmod><changefreq>monthly</changefreq></url><url><loc>https://four-color-theorem.com/2011/02/08/wordpress-sourceforge/</loc><lastmod>2025-01-09T21:58:24+00:00</lastmod><changefreq>monthly</changefreq></url><url><loc>https://four-color-theorem.com/2011/12/22/four-color-theorem-tait-edge-coloring/</loc><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2011/12/map-3edgecolored.png</image:loc><image:title>Map-3EdgeColored</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2011/12/map-4colored.png</image:loc><image:title>Map-4Colored</image:title><image:caption>Four color theorem</image:caption></image:image><lastmod>2025-01-09T21:51:20+00:00</lastmod><changefreq>monthly</changefreq></url><url><loc>https://four-color-theorem.com/software/</loc><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2011/01/last-sourceforge-stats.png</image:loc><image:title>last-sourceforge-stats</image:title></image:image><lastmod>2025-01-08T22:36:54+00:00</lastmod><changefreq>weekly</changefreq><priority>0.6</priority></url><url><loc>https://four-color-theorem.com/me/chess/</loc><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2012/10/gameknot-stats.png</image:loc><image:title>gameknot-stats</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2012/10/spock-chess.jpg</image:loc><image:title>spock-chess</image:title><image:caption>Four color theorem</image:caption></image:image><lastmod>2025-01-08T22:08:44+00:00</lastmod><changefreq>weekly</changefreq><priority>0.6</priority></url><url><loc>https://four-color-theorem.com/t2/</loc><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2025/01/tutte-circles-colored-2.png</image:loc><image:title>tutte-circles-colored-2</image:title></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2011/03/rectangular-maps-some-steps.png</image:loc><image:title>rectangular-maps-some-steps</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2011/02/haken-appel-hardest-case-map-rectangularization-start.png</image:loc><image:title>haken-appel-hardest-case-map-rectangularization-start</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2011/02/new-york-city-skyline.png</image:loc><image:title>new-york-city-skyline</image:title><image:caption>Four color theorem</image:caption></image:image><lastmod>2025-01-08T21:58:03+00:00</lastmod><changefreq>weekly</changefreq><priority>0.6</priority></url><url><loc>https://four-color-theorem.com/me/aikido/</loc><lastmod>2025-01-06T23:39:41+00:00</lastmod><changefreq>weekly</changefreq><priority>0.6</priority></url><url><loc>https://four-color-theorem.com/abstract/</loc><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2011/01/starry-night.png</image:loc><image:title>starry-night</image:title><image:caption>Four color theorem</image:caption></image:image><lastmod>2025-01-05T10:24:31+00:00</lastmod><changefreq>weekly</changefreq><priority>0.6</priority></url><url><loc>https://four-color-theorem.com/introduction/</loc><lastmod>2025-01-05T10:22:48+00:00</lastmod><changefreq>weekly</changefreq><priority>0.6</priority></url><url><loc>https://four-color-theorem.com/t1/</loc><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2011/04/simplify-map-f4-abstract-v2.png</image:loc><image:title>simplify-map-F4-abstract-v2</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2011/04/simplify-map-f4-abstract.png</image:loc><image:title>simplify-map-F4-abstract</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2011/01/simplify-map-f4.png</image:loc><image:title>simplify-map-F4</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2011/01/simplify-map-f3.png</image:loc><image:title>simplify-map-F3</image:title><image:caption>Four color theorem</image:caption></image:image><lastmod>2025-01-05T10:22:07+00:00</lastmod><changefreq>weekly</changefreq><priority>0.6</priority></url><url><loc>https://four-color-theorem.com/2016/02/23/four-color-theorem-back-to-the-basics/</loc><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2016/02/kempe-reduction-and-kempes-chain-v3.png</image:loc><image:title>kempe-reduction-and-kempe's-chain-v3</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2016/02/kempe-reduction-and-kempes-chain-v2.png</image:loc><image:title>kempe-reduction-and-kempe's-chain-v2</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2016/02/kempe-reduction-and-kempes-chain.png</image:loc><image:title>kempe-reduction-and-kempe's-chain</image:title><image:caption>Four color theorem</image:caption></image:image><lastmod>2025-01-04T21:30:08+00:00</lastmod><changefreq>monthly</changefreq></url><url><loc>https://four-color-theorem.com/2022/08/24/3-regular-planar-graph-decomposition-in-cycles-and-4ct/</loc><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2022/08/tait-coloring-and-kempe-cycles-horizontal.jpg</image:loc><image:title>tait-coloring-and-kempe-cycles-horizontal</image:title></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2022/08/tait-coloring-and-kempe-cycles-1.jpg</image:loc><image:title>tait-coloring-and-kempe-cycles</image:title></image:image><lastmod>2022-11-08T21:49:08+00:00</lastmod><changefreq>monthly</changefreq></url><url><loc>https://four-color-theorem.com/2022/08/22/tait-coloring-and-the-four-color-theorem/</loc><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2022/08/image-1.png</image:loc><image:title>image-1</image:title></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2022/08/image.png</image:loc><image:title>image</image:title></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2022/08/tait-coloring-concentric-kempe-chains.jpg</image:loc><image:title>tait-coloring-concentric-kempe-chains</image:title></image:image><lastmod>2022-09-27T21:28:07+00:00</lastmod><changefreq>monthly</changefreq></url><url><loc>https://four-color-theorem.com/2022/09/04/color-voronoi-graphs/</loc><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2022/09/4ct-voronoi-to-3-regular-v2.jpg</image:loc><image:title>4ct-voronoi-to-3-regular-v2</image:title></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2022/09/4ct-voronoi-to-3-regular.jpg</image:loc><image:title>4ct-voronoi-to-3-regular</image:title></image:image><lastmod>2024-04-09T09:33:43+00:00</lastmod><changefreq>monthly</changefreq></url><url><loc>https://four-color-theorem.com/2022/08/23/4ct-and-loops-cycles-circuits-chains-paths/</loc><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2022/08/image-5.png</image:loc><image:title>image-5</image:title></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2022/08/image-4.png</image:loc><image:title>image-4</image:title></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2022/08/image-3.png</image:loc><image:title>image-3</image:title></image:image><lastmod>2022-08-23T21:26:17+00:00</lastmod><changefreq>monthly</changefreq></url><url><loc>https://four-color-theorem.com/2016/11/22/four-color-theorem-what-next/</loc><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2016/11/haken-appel-hardest-case-map.png</image:loc><image:title>haken-appel-hardest-case-map</image:title></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2016/11/planar-non-hamilonian.png</image:loc><image:title>planar-non-hamilonian</image:title></image:image><lastmod>2018-08-19T23:27:47+00:00</lastmod><changefreq>monthly</changefreq></url><url><loc>https://four-color-theorem.com/2018/04/23/large-planar-map-creation-using-python/</loc><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2018/04/map-creation-0-n.jpg</image:loc><image:title>map-creation-0-n</image:title></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2018/04/map-creation-5-n.jpg</image:loc><image:title>map-creation-5-n</image:title></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2018/04/map-creation-4-n.jpg</image:loc><image:title>map-creation-4-n</image:title></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2018/04/map-creation-3-n.jpg</image:loc><image:title>map-creation-3-n</image:title></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2018/04/map-creation-2-n.jpg</image:loc><image:title>map-creation-2-n</image:title></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2018/04/map-creation-1-n.jpg</image:loc><image:title>map-creation-1-n</image:title></image:image><lastmod>2018-04-23T21:57:32+00:00</lastmod><changefreq>monthly</changefreq></url><url><loc>https://four-color-theorem.com/2017/07/18/how-nice-is-docker/</loc><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2017/07/how-nice-is-docker.png</image:loc><image:title>how-nice-is-docker</image:title></image:image><lastmod>2017-07-18T22:04:00+00:00</lastmod><changefreq>monthly</changefreq></url><url><loc>https://four-color-theorem.com/2017/07/09/four-color-theorem-a-fast-algorithm-2/</loc><lastmod>2017-07-09T18:09:29+00:00</lastmod><changefreq>monthly</changefreq></url><url><loc>https://four-color-theorem.com/2017/01/24/four-color-theorem-about-edges-selection/</loc><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2017/01/edges-selection-possibilities.jpg</image:loc><image:title>edges-selection-possibilities</image:title></image:image><lastmod>2017-06-18T20:42:20+00:00</lastmod><changefreq>monthly</changefreq></url><url><loc>https://four-color-theorem.com/2017/05/16/i-moved-the-code-under-github/</loc><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2017/05/github-home.png</image:loc><image:title>github-home</image:title></image:image><lastmod>2017-05-16T21:14:29+00:00</lastmod><changefreq>monthly</changefreq></url><url><loc>https://four-color-theorem.com/2016/12/01/four-color-theorem-new-ideas/</loc><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2016/12/avoid-f5.png</image:loc><image:title>avoid-f5</image:title></image:image><lastmod>2016-12-14T15:12:16+00:00</lastmod><changefreq>monthly</changefreq></url><url><loc>https://four-color-theorem.com/2016/10/25/four-color-theorem-one-switch-is-not-enough/</loc><lastmod>2016-12-02T20:17:24+00:00</lastmod><changefreq>monthly</changefreq></url><url><loc>https://four-color-theorem.com/2016/11/05/four-color-theorem-infinite-switches-are-not-enough-rectangular-map/</loc><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2016/11/really_bad_case-ariadne_step-5-12-7-32-6-15-10-ppt.png</image:loc><image:title>really_bad_case-ariadne_step-5-12-7-32-6-15-10-ppt</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2016/11/save-graph-really-bad-case.png</image:loc><image:title>save-graph-really-bad-case</image:title><image:caption>Four color theorem</image:caption></image:image><lastmod>2016-11-17T18:04:32+00:00</lastmod><changefreq>monthly</changefreq></url><url><loc>https://four-color-theorem.com/2016/05/18/four-color-theorem-sage-and-multiple-edges/</loc><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2016/05/kempe-half-cycle-swapping-method-sage-and-multiple-edges.png</image:loc><image:title>kempe-half-cycle-swapping-method-sage-and-multiple-edges</image:title><image:caption>Four color theorem</image:caption></image:image><lastmod>2016-11-10T16:31:19+00:00</lastmod><changefreq>monthly</changefreq></url><url><loc>https://four-color-theorem.com/2016/10/31/four-color-theorem-infinite-switches-are-not-enough/</loc><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2016/10/really_bad_case-ariadne_step-5-12-7-32-6-15-10.png</image:loc><image:title>really_bad_case-ariadne_step-5-12-7-32-6-15-10</image:title><image:caption>Four color theorem</image:caption></image:image><lastmod>2016-10-31T23:43:13+00:00</lastmod><changefreq>monthly</changefreq></url><url><loc>https://four-color-theorem.com/2016/05/03/four-color-theorem-down-to-a-single-case/</loc><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2016/05/kempe-half-cycle-swapping-method-f5-second-page.png</image:loc><image:title>kempe-half-cycle-swapping-method-F5-second-page</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2016/05/kempe-half-cycle-swapping-method-f5-first-page.png</image:loc><image:title>kempe-half-cycle-swapping-method-F5-first-page</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2016/05/kempe-half-cycle-swapping-method-f5-third-page-v2.png</image:loc><image:title>kempe-half-cycle-swapping-method-F5-third-page-v2</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2016/05/kempe-half-cycle-swapping-method-f5-third-page.png</image:loc><image:title>kempe-half-cycle-swapping-method-F5-third-page</image:title><image:caption>Four color theorem</image:caption></image:image><lastmod>2016-05-03T10:40:41+00:00</lastmod><changefreq>monthly</changefreq></url><url><loc>https://four-color-theorem.com/2016/05/02/four-color-theorem-almost-there/</loc><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2016/05/kempe-half-cycle-swapping-method-f4.png</image:loc><image:title>kempe-half-cycle-swapping-method-F4</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2016/05/kempe-half-cycle-swapping-method.png</image:loc><image:title>kempe-half-cycle-swapping-method</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2016/05/kempe-cycle-f5-both-edges-not-on-cycles.png</image:loc><image:title>kempe-cycle-F5-both-edges-not-on-cycles</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2016/04/kempe-cycle.png</image:loc><image:title>kempe-cycle</image:title><image:caption>Four color theorem</image:caption></image:image><lastmod>2023-09-07T10:15:11+00:00</lastmod><changefreq>monthly</changefreq></url><url><loc>https://four-color-theorem.com/2014/08/27/four-color-theorem-experimenting-impasses-as-in-life/</loc><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2014/08/kempe-chain-deroute-v2.jpg</image:loc><image:title>kempe-chain-deroute-v2</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2014/08/kempe-chain-deroute.jpg</image:loc><image:title>kempe-chain-deroute</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2014/08/impasse-in-map-not-simplified.jpg</image:loc><image:title>impasse-in-map-not-simplified</image:title><image:caption>Four color theorem</image:caption></image:image><lastmod>2015-09-29T19:29:45+00:00</lastmod><changefreq>monthly</changefreq></url><url><loc>https://four-color-theorem.com/2014/08/05/four-color-theorem-counterexample-to-the-hypothesis-i-was-verifying/</loc><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2014/08/hypothesis-counterexample-v2.jpg</image:loc><image:title>hypothesis-counterexample-v2</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2014/08/hypothesis-counterexample.jpg</image:loc><image:title>hypothesis-counterexample</image:title><image:caption>Four color theorem</image:caption></image:image><lastmod>2022-08-11T10:54:40+00:00</lastmod><changefreq>monthly</changefreq></url><url><loc>https://four-color-theorem.com/2012/03/11/four-color-theorem-deep-analysis-of-a-map/</loc><lastmod>2015-01-08T00:04:01+00:00</lastmod><changefreq>monthly</changefreq></url><url><loc>https://four-color-theorem.com/2014/07/14/four-color-theorem-3-edge-coloring-impasse-and-kempe-chain-color-swapping/</loc><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2014/07/impasse-kempe-chain-fallacious-v5.jpg</image:loc><image:title>impasse-kempe-chain-fallacious-v5</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2014/07/impasse-kempe-chain-fallacious-v4.jpg</image:loc><image:title>impasse-kempe-chain-fallacious-v4</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2014/07/impasse-kempe-chain-fallacious-v3.jpg</image:loc><image:title>impasse-kempe-chain-fallacious-v3</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2014/07/impasse-kempe-chain-fallacious-v2.jpg</image:loc><image:title>impasse-kempe-chain-fallacious-v2</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2014/07/tait-and-kempe-coloring-switch-v4.png</image:loc><image:title>tait-and-kempe-coloring-switch-v4</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2014/07/kempe-chain-impasse-v2.png</image:loc><image:title>kempe-chain-impasse-v2</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2014/07/impasse-kempe-chain-fallacious.jpg</image:loc><image:title>impasse-kempe-chain-fallacious</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2014/07/tait-and-kempe-coloring-switch-v3.png</image:loc><image:title>tait-and-kempe-coloring-switch-v3</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2014/07/tait-and-kempe-coloring-switch-v2.png</image:loc><image:title>tait-and-kempe-coloring-switch-v2</image:title><image:caption>Four color theorem</image:caption></image:image><image:image><image:loc>https://four-color-theorem.com/wp-content/uploads/2014/07/tait-and-kempe-coloring-switch.png</image:loc><image:title>tait-and-kempe-coloring-switch</image:title><image:caption>Four 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