摘要
Proposition 1（Clifford Theorem）. Let G be finite. Consider a simple left A-module V. Then V is a finitely generated semisimple left A<sub>1</sub>-module. Let W be a simple left A<sub>1</sub>-submodule of V, and then I={g∈G|A<sub>1</sub>（?）<sub>A<sub>1</sub></sub> W（?）Ag（?）<sub>A<sub>1</sub></sub> W as A<sub>1</sub>-modules}is a subgroup of G, and there exists a natural number e such
