Let D be a subset of Z(mod n) be a (n,k,lambda)-difference set
Let D(complement) = Z(mod n)\D
Prove that any non zero element of Z(mod n) occurs 2(k-lambda) times as a difference of elements, one in D and the other in D(complement)
Let D be a subset of Z(mod n) be a (n,k,lambda)-difference set
Let D(complement) = Z(mod n)\D
Prove that any non zero element of Z(mod n) occurs 2(k-lambda) times as a difference of elements, one in D and the other in D(complement)