Testing set proportionality and the Ádám isomorphism of circulant graphs

Given two k element subsets S,T ⊆ ℤn, we give a quasi-linear algorithm to either find λ ∈ ℤ*n such that S = λT or prove that no such λ exists. This question is closely related to isomorphism testing of circulant graphs and has recently been studied in the literature.12 page(s