Example: The most important example is the topological space <math>S^1</math>. It can be shown that the fundamental group of <math>S^1</math> is isomorphic to the additive group of [[integer]]s <math>\mathbf{Z}</math>. | Example: The most important example is the topological space <math>S^1</math>. It can be shown that the fundamental group of <math>S^1</math> is isomorphic to the additive group of [[integer]]s <math>\mathbf{Z}</math>. |