Puppe sequence

In mathematics, the doll - result is a construction of the homotopy theory.

It was introduced by Dieter doll in 1958.

Definition

It should be a continuous map. It is the mapping of cone, then

A Kofaserung and

Is the device to attach from. By iterating the so-called puppet sequence obtained

Application

For a continuous map form for each room, the homotopy classes of continuous maps an exact sequence