关键词: 模2n 1加, 模2n－1加, 相容性, 相容概率, 计数

Abstract: Consistency of two operations means the error generated in substituting one with the other, or in changing the location and order of two variables in equations that contains both of them. Addition modulo 2n+1 and addition modulo 2n－1 are two code links which are used in cryptography algorithms. This paper analyzed the consistency of addition modulo 2n+1 and addition modulo 2n－1 under equality, distributive law and associative law. According to these three case, the probability formulas of equality, equality under distributive law and equality under associative law are presented. Finally, the consistency characters in different case are given with respect to probability formulas.

Key words: addition modulo 2n 1, addition modulo 2n－1, consistency, consistent probablity, counting