摘要
In 1955, Serre gave an open problem on freeness of projective modules over polynomial ring over a field. In fact, it was proved by Serre in 1958 that if P is a finitely generated projective module over R[x<sub>1</sub>,…, x<sub>n</sub>], then P is stably isomorphic to a free module.
基金
Project supported by the National Natural Science Foundation of China
