Question

difference set term define

Answer 1

hey mate

here is ur answer :-


the difference set of A and B is set A-B in which all elements of A are not included in b bit all element of b is included in A

example :- A (2,3,4,6,8) B (1,3,4,8)


i hope it helps you


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Answer 2

Hey

Here is your answer,

Difference sets are closely connected with block designs (cf. Block design), namely: The existence of a difference set is equivalent to the existence of a symmetric block design with parameters (v,k,λ) having a cyclic group of automorphisms of order v (the blocks of such a design are the sets {d1+i,…,dk+i}, i=0,…,v−1). The notion of a difference set can be generalized in the following way: A set D consisting of k distinct elements d1,…,dk of a group G of order v is called a (v,k,λ)-difference set in G if for any a∈G, a≠1, there exist precisely λ ordered pairs (di,dj), di,dj∈G, such that did−1j=a (or, what is the same, λ pairs (di,dj) with d−1idj=a). In this case a difference set as defined above is called a cyclic difference set (since the group of residue classes modv is a cyclic group). The existence of (v,k,λ)-difference sets in a group G of order v is equivalent to the existence of a symmetric block design with parameters (v,k,λ) admitting G as a regular (that is, without fixed points) group of automorphisms (this design is obtained by identifying the elements of the block design with the elements of the group and the blocks with the sets {d1g,…,dkg}, where g runs over G).

Hope it helps you!