# Graph Coloring, or Proof by Crayon

DevFeed: [Graph Coloring, or Proof by Crayon](<https://devfeed.tech/articles/graph-coloring-or-proof-by-crayon-40226.md>)

Original publisher: [Read original article](<https://www.jeremykun.com/2011/07/14/graph-coloring-or-proof-by-crayon/>)

Published: 2011-07-14T22:24:13Z

Content type: tutorial

Language: en

Sources: [Jeremy Kun](<https://devfeed.tech/sources/jeremy-kun.md>)

Topics: [Graphs](<https://devfeed.tech/topics/graphs.md>), [graph theory](<https://devfeed.tech/topics/graph-theory.md>), [color](<https://devfeed.tech/topics/color.md>), [math](<https://devfeed.tech/topics/math.md>)

Tags: [color](<https://devfeed.tech/tags/color.md>), [graph](<https://devfeed.tech/tags/graph.md>), [graph-coloring](<https://devfeed.tech/tags/graph-coloring.md>), [graph-theory](<https://devfeed.tech/tags/graph-theory.md>), [graphs](<https://devfeed.tech/tags/graphs.md>), [map](<https://devfeed.tech/tags/map.md>), [maps](<https://devfeed.tech/tags/maps.md>), [mathematics](<https://devfeed.tech/tags/mathematics.md>), [primer](<https://devfeed.tech/tags/primer.md>), [pseudocode](<https://devfeed.tech/tags/pseudocode.md>)

## AI overview

This tutorial introduces graph coloring through map-coloring examples, including the provinces of Costa Rica and the arrondissements of Paris. It models adjacent regions as vertices connected by edges, defines a valid graph coloring, and introduces the chromatic number as the smallest number of colors needed.

## Source excerpt

How many colors are required to color the provinces of Costa Rica? A common visual aid for maps is to color the regions of the map differently, so that no two regions which share a border also share a color. For example, to the right is a map of the provinces of Costa Rica (where the author is presently spending his vacation). It is colored with eight different colors, one for each province.