摘要
It is proved that for any r.e. degreesv <u, there exists a properly d-r.e. degreec such thatc is a branching degree andv <c <u.
It is proved that for any r.e. degrees v<u, there exists a properly d-r. e. degree c such that c is a branching degree and v<c<u.
基金
Project supported by the National Natural Science Foundation of China (Grant No. 19771045)
National 863 Hi-Tech R&D Programme.
