triangle graph

{{One source|date=July 2024}}{{Distinguish|Triangular graph|Ternary plot}}

{{infobox graph

| name = Triangle graph

| image = 160px

| image_caption = The triangle graph

| vertices = 3

| edges = 3

| automorphisms = 6 (D₃)

| chromatic_number = 3

| chromatic_index = 3

| diameter = 1

| radius = 1

| girth = 3

| notation = $C\_3$ or $K\_3$

| properties = 2-regular
Vertex-transitive
Edge-transitive
Unit distance
Hamiltonian
Eulerian

}}

In the mathematical field of graph theory, the triangle graph is a planar undirected graph with 3 vertices and 3 edges, in the form of a triangle.{{MathWorld|urlname=TriangleGraph|title=Triangle Graph}}

The triangle graph is also known as the cycle graph $C\_3$ and the complete graph $K\_3$.