n-chromatic graph

A graph G having chromatic number γ(G) = k is called a k-chromatic graph. In contrast, a graph having γ(G)<=k is said to be a k-colorable graph. A graph is one-colorable iff it is totally disconnected (i.e., is an empty graph). The 1, 2, 6, and 8 distinct simple 2-chromatic graphs on n = 2, ..., 5 nodes are illustrated above. The 1, 3, and 16 distinct simple 3-chromatic graphs on n = 3, 4, and 5 nodes are illustrated above. The 1 and 4 distinct simple 4-chromatic graphs on n = 4 and 5 nodes are illustrated above.

chromatic number | chromatic polynomial | k-colorable graph | k-colored graph