幂等自映射的Nielsen数（3）

Nielsen's Number of The Power- Equate Self-Map (3)

设Ｘ是有限且连通的多面体，ｆ是Ｘ上的幂等自映射，则在在Ｘ上同伦于ｆ的自映射，在基本群π１（Ｘ，ｘ０）子群Ｉｍ上的作用是恒同同构。

If X is a finite and connected polyhedron, f is a power-equate self-mapping of X,then there exists self-mapping of X,such that is homotopic to f and restricted to Im .a subgroup of the fundamental group π1 (X,x ), is the identity isomorphism.