Category:Definitions/Euler Characteristic of Finite Graph

This category contains definitions related to Euler Characteristic of Finite Graph.
Related results can be found in Category:Euler Characteristic of Finite Graph.

Let $G = \struct {V, E}$ be a finite graph.

Let $G$ be embedded in a surface.

The Euler characteristic of $G$ is written $\map \chi G$ and is defined as:

$\map \chi G = v - e + f$

where:

$v = \size V$ is the number of vertices

$e = \size E$ is the number of edges

$f$ is the number of faces.