Abstract: From the cryptographic viewpoint, stabilities of period and linear complexity of period sequences are important measures for unpredictability and randomness. Using the rational fraction notation and the minimum polynomial of the sequences, we discuss the stabilities of self-shrinking sequences. The weight period W^Cn(s^∞) and the eight complxity W^Pu(s^∞) of the self-shrinking sequence are given when u is one or two.

Key words: period sequence, self-shrinking sequence, stability of period, stability of linear complexity, weight period