Near Difference Sets of Type 2

Since cyclic difference sets have numerous important applications in thetheories as well as in the practice of experiment designs and communication, theyhave been studied in detail, and a certain number of generalizations andvariants have been investigated extensively. In 1973, H.J. Ryser proposed a     

递归关系的精确表示式

本文给出了变系数线性递归关系解的精确表示式及一些与此相关的结果。     

Equivalence Relation on the Set of Subsets of Z_v and Enumeration of the Equivalence Classes

Motivated by the concept of equivalent cyclic difference sets on Z_v (the residue ring modulo v), we introduce a similar equivalence relation on the set of subsets of Z_v as follows. Difinition Let D_1 and D_2 be two subsets of Z_v. If D_1=tD_2+s for some t, s∈Z_v(ged(t,v)=1), then D_1 and D_2 are said to be equivalent, denoted by D_～D_2.